WO2017090399A1 - Endoscope device - Google Patents

Abstract

This endoscope device is provided with: a leading end unit to be inserted into a subject; a main body unit disposed outside of the subject; an image pickup element disposed in the leading end unit; a first signal conversion unit, which is disposed in the leading end unit, and which converts image output signals transmitted from the image pickup element into first optical signals; an optical transmission unit that transmits light between the leading end unit and the main body unit; a light output unit, which is disposed in the main body unit, and which outputs light to the optical transmission unit; and a first photoelectric conversion unit, which is disposed in the main body unit, and which converts the first optical signals into electric signals, said first optical signals having been transmitted from the first signal conversion unit via the optical transmission unit.

Description

Endoscope device

The present invention relates to an endoscope apparatus.
This application claims priority based on Japanese Patent Application No. 2015-228780 filed in Japan on November 24, 2015, the contents of which are incorporated herein by reference.

Endoscope apparatuses are widely used in the industrial field or the medical field.
For example, industrial endoscopes are used for observation and inspection of internal scratches, corrosion, and the like of subjects such as boilers, turbines, engines, and chemical plants.
In such an industrial endoscope, an imager is disposed at the distal end portion, and a driver circuit for the imager is disposed in the main body portion. A drive signal to the imager is metal-transmitted by an electric wire inserted into an insertion portion between the tip portion and the main body portion. However, when the length of the insertion portion is increased, external noise is likely to ride on the transmission path depending on the use environment.
Since medical endoscope apparatuses are often used together with various medical devices, external noise caused by other medical devices may get on the transmission path.
For example, in Patent Document 1, in order to prevent EMI noise from being mixed, a video output signal of a solid-state imaging device is converted into an optical signal at an imaging tip, and this optical signal is captured via an optical signal cable. An imaging apparatus that transmits data to a computer has been proposed.
In the technique described in Patent Document 1, a VCSEL (Vertical Cavity Surface Emitting Laser) is used as a light source at the imaging tip in order to convert a video output signal into an optical signal.

Japanese Unexamined Patent Application Publication No. 2010-51503

The prior art as described above has the following problems.
The imaging device described in Patent Document 1 includes a VCSEL at the imaging tip. For this reason, a VCSEL driver and a feedback control mechanism for keeping the oscillation intensity and oscillation wavelength of the VCSEL constant need to be disposed near the VCSEL at the imaging front end.
As a result, the imaging apparatus described in Patent Document 1 has a problem that the imaging tip is enlarged and the configuration of the imaging tip is complicated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an endoscope apparatus that is not easily affected by external noise in signal transmission and that can be downsized at the tip. To do.

In order to solve the above problems, an endoscope apparatus according to a first aspect of the present invention includes a distal end portion inserted into a subject, a main body portion disposed outside the subject, and the distal end portion. Between the arranged image pickup device, the first signal conversion unit arranged at the tip portion and converting a video output signal from the image pickup device into a first optical signal, and between the tip portion and the main body portion An optical transmission unit that transmits light; a light emitting unit that is disposed in the main body unit, and that emits light to the optical transmission unit; and is disposed in the main body unit, and the optical transmission unit is connected to the first signal conversion unit. A first photoelectric conversion unit that converts the first optical signal transmitted via the first optical signal into an electrical signal.

According to each of the above aspects, there is an effect that it is difficult to be influenced by external noise in signal transmission and the tip portion can be reduced in size.

It is a block diagram showing an example of composition of an endoscope apparatus concerning a 1st embodiment of the present invention. It is a block diagram which shows the structural example of the endoscope apparatus which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the structural example of the endoscope apparatus which concerns on the 3rd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In all the drawings, even if the embodiments are different, the same or corresponding members are denoted by the same reference numerals, and common description is omitted.

[First Embodiment]
An endoscope apparatus according to a first embodiment of the present invention will be described.
FIG. 1 is a block diagram illustrating a configuration example of an endoscope apparatus according to the first embodiment of the present invention.

As shown in FIG. 1, the endoscope apparatus 11 according to the present embodiment includes an insertion part 400 and a main body part 300. The endoscope apparatus 11 is inserted into the subject and acquires at least an image inside the subject. The type of subject is not particularly limited. For example, the subject of the endoscope apparatus 11 may be an industrial device such as a boiler, a turbine, an engine, a chemical plant, or a living body.

The insertion unit 400 is a device part that is inserted into the subject in the endoscope apparatus 11. The insertion portion 400 is a bendable elongated tube.
The distal end portion 100 is attached to the distal end of the insertion portion 400 in the insertion direction.
The tip portion 100 includes an image sensor 101 and an optical modulator 102 (first signal conversion unit).

The image sensor 101 photoelectrically converts light from the subject.
Although not shown in FIG. 1, the distal end portion 100 is provided with a light-transmitting light receiving window for allowing light from the subject to enter. Further, an objective lens (not shown) that images light from the subject on the imaging surface of the imaging device 101 is disposed between the light receiving window and the imaging device 101.
The type of the image sensor 101 is not particularly limited. Examples of the image sensor 101 include a CMOS image sensor (CIS) and a CCD.
The image sensor 101 performs photoelectric conversion of the received light based on the drive signal and outputs a video output signal Si that is an electrical signal.
The number of drive signals varies depending on the type of the image sensor 101. FIG. 1 shows drive signals Sd1 and Sd2 as an example. The number of drive signals may be three or more.
Examples of the drive signal include a drive clock, a communication signal, and a control signal.
In FIG. 1, the power supply lines of the image sensor 101 and the optical modulator 102 are not shown.

The optical modulator 102 is electrically connected to the image sensor 101 and converts the video output signal Si from the image sensor 101 into an optical signal Li (first optical signal).
The type of the optical modulator 102 is not particularly limited. As an example of a device suitable for the optical modulator 102, a waveguide type optical modulator having a waveguide constituting a Mach-Zehnder interferometer and a phase modulation electrode can be cited. In the waveguide type optical modulator, intensity modulation by light interference is possible by applying a modulation signal to the phase modulation electrode.
The optical modulator 102 having such a configuration is more resistant to environmental temperature changes than the light source 301 described later. For example, the guaranteed operating temperature of the waveguide type optical modulator is −5 ° C. or higher and + 75 ° C. or lower. Therefore, for example, even if the tip 100 is exposed to a temperature environment of about −5 ° C. or higher and + 75 ° C. or lower, it can be used without any trouble.

In this embodiment, input light used for the optical modulator 102 is supplied from the light source 301 of the main body 300 to the optical modulator 102 via the transmission unit 200 described later. For this reason, a light source that generates input light for performing light modulation and a device that drives and controls the light source are not disposed at the distal end portion 100.

In the insertion part 400, the transmission part 200 is inserted into the tubular part extending from the distal end part 100 toward the main body part 300.
The transmission unit 200 performs signal transmission between the distal end unit 100 and a main body unit 300 described later.
In the present embodiment, the transmission unit 200 includes an electric cable 203, an optical fiber 201 (optical transmission unit), and an optical fiber 202 (optical transmission unit).

The electric wire cable 203 transmits the drive signals Sd1 and Sd2 for driving the image sensor 101 to the metal. Although not particularly illustrated, the electric cable 203 may include a power supply line that operates the imaging device 101.

One end of the optical fiber 201 is connected to the output port of the optical modulator 102, and the other end is extended to a main body 300 described later. The optical fiber 201 optically transmits the optical signal Li output from the optical modulator 102 toward the main body 300.
One end of the optical fiber 202 is connected to the input port of the optical modulator 102, and the other end is extended to a main body 300 described later. The optical fiber 202 optically transmits the input light Lλ ₁ generated in the main body 300 to the input port of the optical modulator 102.
For example, a laser beam having a wavelength λ ₁ can be used as the input light Lλ ₁ .

The main body 300 is disposed outside the subject.
The main body 300 includes at least an electrical unit for performing video acquisition by the image sensor 101.
The main body 300 may include at least one of an operation unit (not shown) for operating the endoscope apparatus 11 and a display unit (not shown) for displaying the acquired video. The main body 300 may include an appropriate input / output interface (not shown) in order to perform an operation from the outside of the apparatus and a video output to the outside of the apparatus.
The main body unit 300 of this embodiment includes a control unit 306, a light source 301 (light emitting unit), a light source driving unit 302, a light source control unit 303, a photoelectric conversion unit 304 (first photoelectric conversion unit), and an image processing unit 305. Prepare.

The control unit 306 controls the operation of the image sensor 101. For this reason, the control unit 306 is electrically connected to the image sensor 101 via the electric wire cable 203.
The control unit 306 controls the operation of the image sensor 101 in response to an operation input through an operation unit (not shown) or an input / output interface.

Light source 301 generates light to be used as input light L lambda _1. In this embodiment, a semiconductor laser is used as the light source 301.
The light source 301 is optically connected to the end of the optical fiber 201 on the main body 300 side via an optical coupler (not shown). For this reason, the input light Lλ ₁ generated by the light source 301 is emitted toward the optical fiber 201.
For example, the guaranteed operating temperature of a semiconductor laser that can be used for the light source 301 is 0 ° C. or higher and + 50 ° C. or lower. In the present embodiment, since the light source 301 is disposed in the main body unit 300, the light source 301 is in a substantially room temperature environment and does not go out of the guaranteed operating temperature.

The light source drive unit 302 drives the light source 301 by supplying a drive current to the light source 301.
The light source control unit 303 keeps the oscillation intensity and the oscillation wavelength λ ₁ of the input light Lλ ₁ emitted from the light source 301 constant by feedback control.

The photoelectric conversion unit 304 is optically coupled to the end of the optical fiber 202 on the main body unit 300 side via an optical coupler (not shown). The photoelectric conversion unit 304 receives the optical signal Li transmitted through the optical fiber 202 and performs photoelectric conversion. The photoelectric conversion unit 304 demodulates the optical signal Li into the video output signal Si.
The photoelectric conversion unit 304 is communicably connected to an image processing unit 305 described later in the main body unit 300. The photoelectric conversion unit 304 sends the demodulated video output signal Si to the image processing unit 305.

The image processing unit 305 performs image processing on the video output signal Si sent from the photoelectric conversion unit 304 to generate video data for display.
The generated video data is sent by the image processing unit 305 to a display unit (not shown) provided in the main body unit 300 or provided outside the endoscope apparatus 11.

Next, the operation of the endoscope apparatus 11 will be described focusing on the image acquisition operation.
When an operation input for starting video acquisition is performed through an operation unit (not shown) or the like, each device portion in the main body unit 300 is activated.
When the control unit 306 is activated, the control unit 306 outputs drive signals Sd1 and Sd2. The drive signals Sd1 and Sd2 are metal-transmitted to the image sensor 101 through the electric cable 203.
When the drive signals Sd1 and Sd2 are transmitted to the image sensor 101 by the electric wire cable 203, the image capturing operation of the image sensor 101 is started. The image sensor 101 photoelectrically converts the received light and sends a video output signal Si to the optical modulator 102.

When the light source driving unit 302 is activated, the light source driving unit 302 supplies a driving current to the light source 301. Thus, the light source 301 generates an input light L lambda _1. A part of the input light Lλ ₁ is guided to the light source control unit 303 because it is used for feedback control. The other input light Lλ ₁ is emitted to the optical fiber 201 through an optical coupler (not shown).
When receiving the input light Lλ ₁ , the light source control unit 303 performs feedback control of the oscillation intensity and the oscillation wavelength with respect to the light source 301. Thus, oscillation intensity and oscillation wavelength of the input light L lambda ₁ is kept constant.

The input light Lλ _{1 that} is optically transmitted by the optical fiber 201 is input to the input port of the optical modulator 102 at the distal end portion 100.
Optical modulator 102 receives the video output signal Si from the imaging device 101, the input light L lambda ₁ and the light modulation, and outputs an optical signal Li from the output port.
The optical signal Li enters the optical fiber 202 via an optical coupler (not shown). The optical signal Li is optically transmitted through the optical fiber 202 and input to the photoelectric conversion unit 304 in the main body unit 300.
The photoelectric conversion unit 304 demodulates the video output signal Si by photoelectrically converting the optical signal Li. The demodulated video output signal Si is sent to the image processing unit 305 by the photoelectric conversion unit 304.
The image processing unit 305 performs image processing on the received video output signal Si, generates video data, and sends it to a display unit (not shown). As a result, an image captured by the image sensor 101 is displayed on a display unit (not shown).

As described above, in the endoscope apparatus 11 of the present embodiment, the video output signal Si of the video imaged at the distal end portion 100 is converted into the optical signal Li at the distal end portion 100 and passes through the optical fiber 202. Thus, optical transmission is performed to the main body 300. For this reason, compared to the case where the video output signal Si is metal-transmitted in the transmission unit 200, external noise is less likely to be applied to the video output signal Si, so that a high-quality video is transmitted.
In the present embodiment, the input light L lambda ₁ when signal conversion video output signal Si to the optical signal Li is to be generated by the light source 301 of the main body portion 300, the inside of the tip 100, the light source and its drive, A control circuit or the like is not arranged. For this reason, compared with the case where a light source and its drive / control circuit are arranged at the tip portion 100, the configuration of the tip portion 100 is simplified and the size can be reduced.
Thus, according to the configuration of the endoscope apparatus 11, it is difficult to be affected by external noise in signal transmission, and the distal end portion 100 can be downsized.

Furthermore, in the present embodiment, the light source 301 having a low temperature resistance is not disposed at the distal end portion 100, and the light modulator 102 having a higher temperature resistance than the light source 301 is disposed. For this reason, the operation guarantee temperature range of the front end portion 100 becomes wider than in the case where the photoelectric conversion portion 103 is included in the front end portion 100.

[Second Embodiment]
An endoscope apparatus according to a second embodiment of the present invention will be described.
FIG. 2 is a block diagram illustrating a configuration example of an endoscope apparatus according to the second embodiment of the present invention.

As shown in FIG. 2, the endoscope apparatus 12 according to the present embodiment includes an insertion unit 400 and a main body unit 300 as in the first embodiment. However, the internal configuration of the insertion unit 400 and the main body unit 300 is different from the configuration of the first embodiment. Hereinafter, a description will be given centering on differences from the first embodiment.

Inside the distal end portion 100 attached to the insertion portion 400 of the present embodiment, an image sensor 101 and an optical modulator 102 similar to the distal end portion 100 of the first embodiment are disposed. Furthermore, a demultiplexer 105 (demultiplexing unit) and photoelectric conversion units 103 and 104 (second photoelectric conversion unit) are added inside the distal end portion 100 of the present embodiment.
In the insertion unit 400, a transmission unit 210 is disposed between the main body unit 300 and the distal end unit 100 in place of the transmission unit 200 in the first embodiment. In the transmission unit 210, the electric cable 203 is deleted from the transmission unit 200 in the first embodiment.
As will be described later, in the present embodiment, the drive signals Sd1 and Sd2 that are metal-transmitted by the electric wire cable 203 in the first embodiment are converted into optical signals in the main body 300, whereby the transmission signal in the transmission unit 210 is obtained. Is transmitted through the optical fiber 201.

The demultiplexer 105 demultiplexes the light input to the input port into light for each wavelength, and outputs the demultiplexed light to different output ports.
The optical fiber 201 of the transmission unit 210 is connected to the input port of the duplexer 105.
The optical modulator 102, the photoelectric conversion unit 103, and the photoelectric conversion unit 104 are connected to the plurality of output ports of the duplexer 105, respectively.
In this embodiment, as will be described later, three types of optical signals based on light of wavelengths λ ₁ , λ ₂ , and λ ₃ are combined and transmitted to the optical fiber 201. Optical signal having the wavelength lambda ₁ input to the demultiplexer 105 is output to the output port of the optical modulator 102 is connected. The optical signal of wavelength λ ₂ input to the duplexer 105 is output to the output port to which the photoelectric conversion unit 103 is connected. The optical signal having the wavelength λ ₃ input to the duplexer 105 is output to the output port to which the photoelectric conversion unit 104 is connected.

The type of the demultiplexer 105 is not particularly limited. For example, a configuration example suitable for the duplexer 105 includes a device such as an AWG (Arrayed Waveguide Grating) filter.
In the AWG filter, a plurality of curved channel waveguides having different lengths are formed between an input-side slab waveguide and an output-side slab waveguide. The light incident on the input slab waveguide of the AWG filter is demultiplexed and emitted from the output slab waveguide.
For example, the operation guarantee temperature of the AWG filter is −40 ° C. or higher and + 85 ° C. or lower. Therefore, for example, even if the tip 100 is exposed to a temperature environment of about −40 ° C. or higher and + 85 ° C. or lower, it can be used without any trouble.

The photoelectric conversion unit 103 is optically coupled to an output port from which an optical signal having a wavelength λ ₂ is emitted from the duplexer 105. The photoelectric conversion unit 103 photoelectrically converts the optical signal Lλ ₂ (second optical signal) having the wavelength λ ₂ from the duplexer 105. As described below, the optical signal L lambda _2, the drive signal Sd1 is a signal converted into an optical signal generated by the control unit 306.
The photoelectric conversion unit 103 is electrically connected to the image sensor 101 and sends a drive signal Sd1 demodulated by photoelectric conversion to the image sensor 101.

The photoelectric conversion unit 104 is optically coupled to an output port from which an optical signal having a wavelength λ ₃ is emitted from the duplexer 105. The photoelectric conversion unit 104 photoelectrically converts the optical signal Lλ ₃ (second optical signal) having the wavelength λ ₃ from the duplexer 105. As described below, the optical signal L lambda _3, the drive signal Sd2 is a signal converted into an optical signal generated by the control unit 306.
The photoelectric conversion unit 104 is electrically connected to the image sensor 101 and sends the drive signal Sd2 demodulated by the photoelectric conversion to the image sensor 101.

Inside the main body unit 300 of the present embodiment, as in the main body unit 300 of the first embodiment, a photoelectric conversion unit 304, an image processing unit 305, a light source 301, a light source driving unit 302, a light source control unit 303, and a control A part 306 is arranged. Further, in the main body 300 of the present embodiment, light sources 307 and 310, light source driving units 308 and 311, light source control units 309 and 312, optical modulators 313 and 314 (second signal conversion unit), and a combination are provided. A waver 315 (multiplexing unit, light emitting unit) is added.

The light sources 307 and 310 generate light having wavelengths λ ₂ and λ ₃ , respectively. In the present embodiment, semiconductor lasers are used as the light sources 307 and 310.
The light sources 307 and 310 are optically connected to input ports of optical modulators 313 and 314 described later via optical couplers (not shown), respectively.

The light source driver 308 (311) supplies a drive current to the light source 307 (310) to drive the light source 301 (310).
The light source control unit 309 (312) keeps the oscillation intensity and oscillation wavelength of the laser light having the wavelength λ ₁ (λ ₂ ) emitted from the light source 307 (310) constant by feedback control.

In the optical modulator 313 (314), a light source 307 (310) is optically connected to an input port, and an input port of a multiplexer 315 described later is optically connected to an output port.
The optical modulator 313 (314) is electrically connected to the control unit 306, and receives the drive signal Sd1 (Sd2) sent from the control unit 306.
The optical modulator 313 (314) optically modulates the laser beam input from the light source 307 (310) based on the drive signal Sd1 (Sd2) input from the control unit 306, and the optical signal Lλ ₂ (Lλ ₃ ). Is generated. The generated optical signal Lλ ₂ (Lλ ₃ ) is sent to the multiplexer 315.

The multiplexer 315 multiplexes a plurality of lights input to the input port and outputs them to the output port.
A light source 301 and optical modulators 313 and 314 are optically connected to an input port of the multiplexer 315. The optical fiber 201 of the transmission unit 210 is connected to the output port of the multiplexer 315.
The multiplexer 315 multiplexes the optical signals Lλ ₁ , Lλ ₂ , and Lλ ₃ transmitted from the light source 301 and the optical modulators 313 and 314 and emits the optical signal Lm to the optical fiber 201.
The type of the multiplexer 315 is not particularly limited. For example, a device such as an AWG filter similar to the duplexer 105 may be used.

In the present embodiment, the light sources 301, 307, and 309 constitute a light source unit that generates a plurality of lights having different wavelength components.
The optical modulators 313 and 314 include second signal converters that convert the drive signals Sd1 and Sd2 for driving the image sensor 101 into optical signals Lλ ₂ and Lλ ₃ (second optical signals) using a plurality of lights. Constitute.
The multiplexer 315 constitutes a multiplexing unit that multiplexes a plurality of lights including the optical signals Lλ ₂ and Lλ ₃ generated by the second signal conversion unit and outputs them to the transmission unit 210.
The configuration including the light source unit, the second signal conversion unit, and the multiplexing unit constitutes a light emitting unit that is disposed in the main body unit 300 and emits light to the optical fiber 201 that is an optical transmission unit.
The photoelectric conversion units 103 and 104 are arranged at the distal end portion 100, and convert the optical signals Lλ ₂ and Lλ ₃ out of the light demultiplexed by the demultiplexer 105 into electrical signals and send them to the image sensor 101. The photoelectric conversion unit is configured.

Next, the operation of the endoscope apparatus 12 will be described focusing on the image acquisition operation, focusing on differences from the first embodiment.
When an operation input for starting video acquisition is performed through an operation unit (not shown) or the like, each device portion in the main body unit 300 is activated.
In the first embodiment, when the control unit 306 is activated, the control unit 306 metal-transmits the drive signals Sd1 and Sd2 to the image sensor 101 via the electric wire cable 203. However, in the present embodiment, the drive signals Sd1 and Sd2 are first converted into optical signals Lλ ₂ and Lλ ₃ by optical modulators 313 and 314, respectively.
The optical signals Lλ ₂ and Lλ ₃ are respectively input to a plurality of input ports of the multiplexer 315.
On the other hand, the input light Lλ ₁ generated by the light source 301 is also input to the input port of the multiplexer 315 in the same manner as in the first embodiment.
Therefore, the optical signal Lm obtained by combining the input light Lλ ₁ , the optical signals Lλ ₂ , and Lλ ₃ is emitted from the output port of the multiplexer 315 to the end of the optical fiber 201.
The optical fiber 201 optically transmits the optical signal Lm to the duplexer 105 in the distal end portion 100.

The demultiplexer 105 demultiplexes the optical signal Lm optically transmitted through the optical fiber 201 for each wavelength, and outputs optical signals Lλ ₂ , Lλ ₃ , and input light Lλ ₁ . The output optical signals Lλ ₂ and Lλ ₃ and the input light Lλ ₁ are input to the photoelectric conversion units 103 and 104 and the optical modulator 102, respectively.
The photoelectric conversion unit 103 and 104, respectively, the optical signal L lambda _2, the photoelectrically converted L lambda _3, demodulates the driving signals Sd1, Sd2. The drive signals Sd1 and Sd2 are input to the image sensor 101, and the image sensor 101 is driven in the same manner as in the first embodiment.
Optical modulator 102 in the same manner as in the first embodiment, when receiving the video output signal Si from the imaging device 101, the input light L lambda ₁ and the light modulation, and outputs an optical signal Li from the output port.
The optical signal Li is transmitted through the optical fiber 202 and demodulated into the video output signal Si by the photoelectric conversion unit 304 in the same manner as in the first embodiment. The video output signal Si is sent to the image processing unit 305 as in the first embodiment, and a video based on the video output signal Si is displayed on a display unit (not shown).

As described above, in the endoscope apparatus 12 according to the present embodiment, the video output signal Si of the video imaged at the distal end portion 100 is transmitted via the optical fiber 202, as in the first embodiment. Optical transmission is performed to the main body 300.
Further, in the present embodiment, drive signals Sd1 and Sd2 sent from the control unit 306 in the main body 300 are converted into optical signals Lλ ₂ and Lλ ₃ and combined with the input light Lλ ₁ . The combined optical signal Lm is sent to the distal end portion 100 via the optical fiber 201 in the transmission unit 210, is photoelectrically converted in the distal end portion 100, and the drive signals Sd1 and Sd2 are demodulated to the image sensor 101. Entered.
Thus, the video output signal Si, the driving signals Sd1, Sd2, the optical signal Li is in the transmission section 210, L lambda _2, is the optical transmission as L lambda _3. As a result, compared to the case where the video output signal Si and the drive signals Sd1 and Sd2 are metal-transmitted in the transmission unit 210, external noise is less likely to be applied to the video output signal Si and the drive signals Sd1 and Sd2, so that a high-quality video can be obtained. Is transmitted.
In the present embodiment, the input light Lλ ₁ and the optical signals Lλ ₂ and Lλ ₃ when the video output signal Si is converted into the optical signal Li are generated by the light sources 301, 307 and 310 in the main body 300. Therefore, the light source and its drive / control circuit are not arranged in the tip portion 100. For this reason, compared with the case where a light source and its drive / control circuit are arranged at the tip portion 100, the configuration of the tip portion 100 is simplified and the size can be reduced.
Thus, according to the configuration of the endoscope apparatus 12, it is difficult to be affected by external noise in signal transmission, and the distal end portion 100 can be downsized.

Furthermore, in this embodiment, the light source 301 having a low temperature resistance is not disposed at the distal end portion 100, but the light modulator 102 and the duplexer 105 having a temperature resistance higher than that of the light source 301 are disposed. For this reason, the operation guarantee temperature range of the front end portion 100 becomes wider than in the case where the photoelectric conversion portion 103 is included in the front end portion 100.

[Third Embodiment]
An endoscope apparatus according to a third embodiment of the present invention will be described.
FIG. 3 is a block diagram illustrating a configuration example of an endoscope apparatus according to the third embodiment of the present invention.

As shown in FIG. 3, the endoscope apparatus 13 according to the present embodiment includes an insertion part 400 and a main body part 300 as in the second embodiment. However, the internal configuration of the main body 300 is different from the configuration of the second embodiment. Hereinafter, the points different from the first and second embodiments will be mainly described.

In the main body 300 of the present embodiment, a multi-wavelength light source is used instead of the light sources 307 and 310, the light source driving units 308 and 311 and the light source control units 309 and 312 in the main body 300 of the second embodiment. A generator 316 and a duplexer 317 are provided.

The multi-wavelength light source generator 316 generates light having a plurality of wavelengths, for example, wavelengths λ ₁ , λ ₂ , and λ _{3 from} the light having the wavelength λ ₁ generated by the light source 301.
The configuration of the multi-wavelength light source generator 316 is not particularly limited as long as it can generate light having wavelengths λ ₁ , λ ₂ , and λ ₃ . For example, the multi-wavelength light source generator 316 may use an optical frequency comb generator.
For example, an optical frequency comb generator has a waveguide formed in an electro-optic crystal and a modulation electrode that applies a modulation signal to the waveguide, and the light incident on the waveguide is centered on the wavelength of the incident light. An optical frequency comb is generated.
For this reason, when light of wavelength λ1 is incident on multiwavelength light source generator 316, light including components of wavelengths λ ₁ , λ ₂ , and λ ₃ is output according to the spectrum of the optical frequency comb.

Similar to the demultiplexer 105, the demultiplexer 317 demultiplexes the input light into light for each of the wavelengths λ ₁ , λ ₂ , and λ ₃ . A device having the same configuration as that of the duplexer 105 can be used as the duplexer 317.
The output port of the multi-wavelength light source generator 316 is connected to the input port of the duplexer 317.
Of the output ports of the duplexer 317, the output port from which light of wavelength λ ₁ is emitted is optically connected to the input port of the multiplexer 315. The light having the wavelength λ ₁ is used for signal conversion of the video output signal Si into the optical signal Li, similarly to the input light Lλ ₁ in the second embodiment.
Of the output ports of the demultiplexer 317, an output port from which light of wavelength λ ₂ (λ ₃ ) is emitted is optically connected to an input port of the optical modulator 313 (314) similar to that of the second embodiment. Connected. The light with the wavelength λ ₂ (λ ₃ ) is used for signal conversion of the drive signal Sd1 (Sd2) into the optical signal Lλ ₂ (Lλ ₃ ) in the same manner as in the second embodiment.

The endoscope apparatus 13 according to this embodiment includes a light source unit including a light source 301 that is a single light source and a multi-wavelength light source generator 316 that is an optical frequency comb generator.

As described above, in the endoscope apparatus 13 according to the present embodiment, the endoscope apparatus 12 according to the second embodiment has the wavelength λ ₁ incident on the multiplexer 315 in the main body 300. The light of λ ₂ and λ ₃ is generated by the light sources 301, 307, and 309, respectively, but the light source 301 that is a single light source is different.
Therefore, according to the configuration of the endoscope apparatus 13 according to the present embodiment, similarly to the endoscope apparatus 12 according to the second embodiment, the distal end portion 100 is hardly affected by external noise in signal transmission. Can be miniaturized.
In particular, according to the present embodiment, since the number of light sources and the number of drive / control circuits in the main body 300 can be reduced, the main body 300 can be reduced in size and simplified.

As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit of the present invention.
Further, the present invention is not limited by the above description, and is limited only by the appended claims.

According to each of the above embodiments, it is possible to provide an endoscope apparatus that is not easily affected by external noise in signal transmission and that can reduce the size of the tip.

11, 12, 13 Endoscope apparatus 100 Tip section 101 Imaging element 102 Optical modulator (first signal conversion section)
103, 104 Photoelectric conversion unit (second photoelectric conversion unit)
105 Demultiplexer (Demultiplexer, AWG filter)
200, 210 Transmission unit 201, 202 Optical fiber (optical transmission unit)
300 Main body 301, 307, 310 Light source (light emitting part)
302, 308, 311 Light source drive units 303, 309, 312 Light source control unit 304 Photoelectric conversion unit (first photoelectric conversion unit)
306 Control unit 313, 314 Light modulator (light emitting unit)
315 multiplexer (light emitting part)
316 Multi-wavelength light source generator (optical frequency comb generator, light output unit)
317 demultiplexer (light emitting part)
Li optical signal (first optical signal)
Lλ ₂ , Lλ ₃ optical signal (second optical signal)
Lλ ₁ input light Sd1, Sd2 drive signal Si video output signal

Claims (7)

A tip inserted into the subject;
A main body disposed outside the subject;
An image sensor disposed at the tip,
A first signal conversion unit that is disposed at the tip and converts a video output signal from the image sensor into a first optical signal;
An optical transmission part for transmitting light between the tip part and the main body part;
A light emitting portion disposed in the main body portion and emitting light to the light transmission portion;
A first photoelectric conversion unit that is disposed in the main body unit and converts the first optical signal transmitted from the first signal conversion unit via the optical transmission unit into an electrical signal;
An endoscopic device comprising: The first signal converter is an optical modulator;
The endoscope apparatus according to claim 1. The light emitting part is
A light source unit that generates a plurality of light components having different wavelength components;
A second signal converter that converts a drive signal for driving the image sensor into a second optical signal using the plurality of lights;
A multiplexing unit that multiplexes a plurality of lights including the second optical signal generated by the second signal conversion unit and outputs the multiplexed light to the optical transmission unit;
With
The tip is
A demultiplexing unit that demultiplexes a plurality of lights including the second optical signal transmitted through the optical transmission unit for each wavelength component;
A second photoelectric conversion unit that is arranged at the tip and converts the second optical signal into an electric signal out of the light demultiplexed by the demultiplexing unit, and sends the electric signal to the image sensor;
Further comprising
The endoscope apparatus according to claim 1 or 2. The second signal converter is an optical modulator.
The endoscope apparatus according to claim 3. The branching unit is an AWG filter.
The endoscope apparatus according to claim 3 or 4. The light source unit is
Generating the plurality of lights using a single light source;
The endoscope apparatus according to any one of claims 3 to 5. The light source unit is
An optical frequency comb generator for generating a plurality of lights having different wavelength components from the light generated by the single light source;
The endoscope apparatus according to claim 6.

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