CN100505813C - scanner driven by bus power supply - Google Patents

Abstract

A scanner driven by bus power supply uses charge coupled device as its photosensitive element. The scanner at least comprises: the device comprises a bus line, a white light emitting component, a driving component and a control component. The bus line is used for connecting the scanner and the computer host, and the computer host provides a bus power supply for the scanner to use through the bus line; the white light emitting component is configured in the scanner and uses a bus power supply so as to provide an irradiation light source required by the scanner in the image scanning process; the driving part is configured in the scanner, and the driving part uses a bus power supply so as to realize various functions; and the control component is configured in the scanner and enables the bus power supply to be used for starting the white light emitting component in a first time period and then enables the bus power supply to be used for the white light emitting component to continuously emit light and be used by the driving component in a second time period.

Description

Scanner powered by bus

technical field

The present invention relates to a scanner, and more particularly to a scanner driven by bus power.

Background technique

Among the many peripheral devices of personal computers, the scanner can be said to be one of the basic equipment, especially the scanner with a charge coupled device (CCD) as the photosensitive element (hereinafter referred to as CCD scanner). The quality and speed of the scanned documents of the CCD scanners launched by various manufacturers are not much different. Therefore, how to make the CCD scanner more convenient to use has become another selling point to attract consumers.

Please refer to FIG. 1 , which shows a schematic diagram of the internal structure of a CCD scanner. The stepping motor 110 can rotate along the direction of the arrow as shown in the figure. The cold cathode fluorescent lamp (cold cathode fluorescent lamp, CCFL) (or discharge lamp (discharged lamp)) 130 is driven by the belt 120, so that the cold cathode tube 130 can move in the direction of the arrow in the figure, and the cold cathode tube 130 can be moved The emitted light irradiates a corresponding position on the document 140 . When the cold cathode tube 130 is in the state of emitting light, and moves from the top of the document 140 to the bottom of the document 140, the entire document 140 will be completely scanned once. The light irradiated on the document 140 is reflected by the reflector 150 to reflect the light beam, and then focused by the lens 155 to the charge-coupled device (hereinafter referred to as CCD) 160 . After the CCD 160 converts light beams of different strengths into current signals of different strengths, the current signals are input into an analog/digital converter (not shown in the figure). Afterwards, the analog/digital converter converts the analog signal of the current into a digital signal and transmits it to the host computer. According to this step, with the movement of the cold cathode tube 130 , the documents 140 are completely scanned from top to bottom one by one, and then the images of the scanned documents 140 are displayed on the computer monitor.

Traditional CCD scanners require electric power from an external power source (self power) to provide operating electric power for internal electronic components such as the cold cathode tube 130, the stepping motor 110 and the CCD 160. However, because the CCD scanner must use a set of power lines and an external power supply to provide electric power in the process of receiving electric power, it is often subject to some restrictions in use.

As can be seen from the above, the traditional CCD scanner has the following disadvantages:

1. The overall structure is relatively complicated: the traditional CCD scanner, because its electric power source is an external power supply, so the CCD scanner itself must be equipped with an additional set of power lines to connect to the external power supply. Because of this, its overall structure is relatively complex.

2. The use must be limited by the existence of an external power supply: traditional CCD scanners must use an external power supply as the source of working electrical power. Therefore, the use is limited by the presence or absence of an external power supply. If the external power supply does not exist, it will inevitably cause the dilemma of not being able to use it.

Contents of the invention

In view of this, the object of the present invention is to provide a scanner driven by bus power, the purpose is as follows:

1. Simplify the overall structure of the CCD scanner.

2. The use of the CCD scanner is no longer limited by the presence or absence of an external power supply.

According to above-mentioned many purposes, the present invention proposes a kind of scanner driven by bus power supply, now briefly describe as follows with respect to its structural feature:

A scanner driven by a bus power supply uses a charge-coupled device as its photosensitive element. The scanner at least includes: bus lines, white light emitting components, driving components and control components. The bus line is used to connect the scanner and the computer host, and the computer host provides bus power through the bus line for the scanner to use; the white light emitting part is arranged in the scanner, and the white light emitting part uses the bus power, so as to provide the scanner in the The irradiation light source required in the image scanning process; the driving part is arranged in the scanner, and the driving part uses the bus power supply to realize various functions; and the control part is arranged in the scanner, and the control part makes the bus power supply in the first A period of time is used for starting the white light emitting component, and the bus power supply is continued to be used for the white light emitting component to continuously emit light and drive components in the second period of time.

In order to make the above objects, features, and advantages of the present invention more comprehensible, preferred embodiments are specifically cited below, together with the accompanying drawings, and described in detail as follows.

Description of drawings

Figure 1 shows a schematic diagram of the internal structure of a CCD scanner.

FIG. 2 shows a schematic diagram of a CCD scanner and a computer host providing electric power according to a preferred embodiment of the present invention.

FIG. 3A shows a block diagram of a control circuit for managing bus power in the CCD scanner of FIG. 2 .

FIG. 3B is a graph showing the relationship between control signals output by the ASIC in FIG. 3A and time.

FIG. 3C is a diagram showing the relationship between power and time provided by the bus power supply to the cold cathode tube in FIG. 3A.

FIG. 4A shows a block diagram of another control circuit for managing bus power in the CCD scanner of FIG. 2 .

FIG. 4B is a graph showing the relationship between control signals output by the ASIC in FIG. 4A and time.

FIG. 4C is a diagram showing the relationship between power and time provided by the bus power supply to the cold cathode tube in FIG. 4A.

Explanation of reference numbers

110: stepper motor

120: belt

130, 330: cold cathode tube

140: File

150: Mirror

155: lens

160: CCD

200, 400: CCD scanner

210: computer host

220: bus line

310, 410: ASIC

320: Inverter to start the lamp

340: Inverter to keep the lamp on

350: stepping motor/CCD

420: Inverter

Detailed ways

The CCD scanner provided by the present invention, its required working electric power is the bus power supply (bus power) that the USB interface that comes from computer host computer provides. The electric power required by the traditional CCD scanner comes from an external power supply. Therefore, the traditional CCD scanner must be equipped with an additional set of power lines for power transmission, so the overall structure is relatively complicated and not simple enough. Moreover, the existence of an external power supply must be taken into account in the use of traditional CCD scanners, so there are often some limitations in use. In the CCD scanner of the present invention, the required electric power can be transmitted to the CCD scanner by the host computer through the bus line connecting the USB interface of the computer host to the CCD scanner. In addition to the purpose of electric power transmission, the bus line also has the function of transmitting signals between the computer host and the CCD scanner. Therefore, the CCD scanner of the present invention will be able to effectively improve the many shortcomings of the traditional CCD scanner, so that the overall structure of the CCD scanner can be simplified, and it is no longer limited by the existence of an external power supply and can be more conveniently use.

Please refer to FIG. 2 , which shows a schematic diagram of a CCD scanner and a computer host providing electric power according to a preferred embodiment of the present invention. The CCD scanner 200 obtains power and data required for work from the host computer 210 through the bus line 220 connected to the USB interface of the host computer 210 . The bus line 220 contains four wires, namely "power" wire, "GND" wire, "data+" wire and "data-" wire, wherein the "power" wire and "GND" wire are used for electric power transmission, and the "data+" wire is used for power transmission. The " line and the "data-" line are used for signal transmission between the CCD scanner 200 and the host computer 210 .

The above-mentioned bus power supply can only provide 2.5W electric power, which is only enough to start the cold cathode tube or discharge lamp used as the illuminating element in the CCD scanner 200 . If the cold cathode tube or the discharge lamp tube still uses the electric power 2.5W that all bus power supplies can provide to maintain its required brightness in the image scanning process after starting, then other electronic components (such as steppers) in the CCD scanner 200 Motor and CCD), because there is no redundant electric power available for use, it is bound to fail to work, and the work of image scanning will not be carried out smoothly.

Therefore the present inventor proposes two kinds of control circuits for managing the bus power in the CCD scanner in the present invention, so that the CCD scanner of the present invention can use the bus line to obtain the required electric power by the computer host, and can fully display the image. Scan function.

Please refer to FIG. 3A , which shows a block diagram of a control circuit for managing the bus power in the CCD scanner of FIG. 2 . The CCD scanner 200 includes an application specific integrated circuit (ASIC) 310, an inverter (inverter) 320 for starting the lamp, an inverter 340 for keeping the lamp on, and a cold cathode tube 330 (or discharge lamp). tube), stepping motor/CCD350. The scanner 200 is connected to the USB interface (not shown) of the host computer 210 through the bus line 220 , that is, the host computer 210 provides bus power for the scanner 200 through the USB interface.

Please refer to FIG. 3A , FIG. 3B and FIG. 3C at the same time. The ASIC 310 in the scanner 200 outputs a high-level signal during the first time period to make the inverter 320 work. The inverter 320 converts the DC voltage provided by the bus power supply into a high-frequency high-voltage power supply for starting the cold-cathode tube 330 . In this period of time, the power obtained by the cold cathode tube 330 is about 2.5W, which is the total power that the bus power supply can provide.

After the cold cathode tube 330 is turned on by the inverter 320 in the first time period, the ASIC 310 continues to output a low-level signal in the second time period to make the inverter 340 work. Similarly, the inverter 340 converts the DC voltage provided by the bus power supply into a high-frequency high-voltage power supply for the cold-cathode tube 330 to maintain a scannable state. In this time period, the cold cathode tube 330 obtains about 0.5W of power from the bus power supply. Therefore, in the second period of time, the remaining power of about 2W of the bus power supply can be provided to the stepper motor/CCD 350 or other drive components that require electric power to operate.

Please refer to FIG. 4A , which shows another block diagram of a control circuit for managing the bus power in the CCD scanner of FIG. 2 . The CCD scanner 400 includes an ASIC 410, an inverter 420, a cold cathode tube 330 (or a discharge lamp), and a stepping motor/CCD 350. The scanner 400 is connected to the USB interface (not shown) of the host computer 210 through the bus line 220 , that is, the host computer 210 provides bus power for the scanner 400 through the USB interface.

Please refer to FIG. 4A , FIG. 4B and FIG. 4C at the same time. The ASIC 410 in the scanner 400 outputs a signal during the first time period to make the inverter 420 function. The inverter 420 converts the DC voltage provided by the bus power supply into a high-frequency high-voltage power supply for starting the cold-cathode tube 330 . In this period of time, the power obtained by the cold cathode tube 330 is about 2.5W, which is the total power that the bus power supply can provide.

After the cold cathode tube 330 is turned on by the inverter 420 in the first time period, the ASIC 410 continues to use pulse width modulation (PWM) to gradually reduce the power supplied to the inverter in the second time period. The inverter 420 converts the low-power direct current provided by the bus power supply into a high-frequency high-voltage power supply for the cold-cathode tube 330 to maintain a scannable state. In this period of time, the cold cathode tube 330 also obtains about 0.5W of power from the bus power supply. Therefore, in the second period of time, the remaining power of about 2W of the bus power supply can be provided to the stepper motor/CCD 350 or other drive components that require electric power to operate.

The above two kinds of control circuits for managing the bus power in the CCD scanner are all enabling the CCD scanner of the present invention to perform the proper function of image scanning. All electronic components in the CCD scanner can obtain the electric power provided by the bus power supply from the USB interface of the host computer and work normally.

The driving method disclosed in the above embodiments of the present invention has at least the following advantages:

1. The overall structure is simple: the CCD scanner of the present invention, because its electric power source is the bus power supply of the USB interface of the computer host, so the CCD scanner itself does not need an additional set of power lines to be connected with an external power supply. Therefore, its overall structure is quite simple.

2. The use is not limited by the presence or absence of an external power supply: the CCD scanner of the present invention, whose electric power source is the bus power supply of the USB interface of the computer host, does not need to use an external power supply as the source of working electric power. Therefore, the use is not limited by the presence or absence of an external power supply.

In summary, although the present invention has been disclosed as above with embodiments, it is not intended to limit the present invention. Any person skilled in the art may make various modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope defined by the proposed claims.

Claims (14)

1. scanner that drives with bus power source is to be its photo-sensitive cell with charge coupled device, and this scanner comprises at least:

One bus line is connected with the USB interface of main frame, and in order to connect this scanner and a main frame, this main frame is to provide a bus power source to use for this scanner by this bus line;

One white-light emitting parts are disposed in this scanner, and these white-light emitting parts use this bus power source, and this scanner required radiation source in the image scanning process is provided according to this;

A plurality of driver parts are disposed in this scanner, and those driver parts use this bus power source, realize various functions according to this; And

One control assembly, be disposed in this scanner, this control assembly make this bus power source in a very first time section for the usefulness of this white-light emitting parts startups, continuous this bus power source that makes is lasting luminous and for those driver parts uses for these white-light emitting parts in one second time period

Wherein, described scanner more comprises an inverter, this inverter is in order to being that a high-frequency and high-voltage power supply is for this white-light emitting parts utilization with the direct current voltage transitions that this bus power source provided, wherein, this bus power source of this second time period power of offering the white-light emitting parts offers the power of these white-light emitting parts less than this bus power source of this very first time section.

2. scanner as claimed in claim 1, wherein, these white-light emitting parts are cold-cathode tubes.

3. scanner as claimed in claim 1, wherein, these white-light emitting parts are discharge lamps.

4. scanner as claimed in claim 1, wherein one of them of those driver parts is stepper motor.

5. scanner as claimed in claim 1, wherein, one of them of those driver parts is charge coupled device.

6. scanner as claimed in claim 1, wherein, this control assembly is an application-specific integrated circuit (ASIC).

7. the method for a management bus power supply, be used in one with charge coupled device in the scanner of its photo-sensitive cell, this scanner has a control assembly, one first converting member, one second converting member and white-light emitting parts, this method comprises:

USB interface by main frame provides this bus power source in this scanner;

This control assembly is exported a high level signal in a very first time section, to make this first converting member effect;

This first converting member is one first high-frequency and high-voltage power supply with the direct current voltage transitions that this bus power source provided, for the usefulness of this white-light emitting parts startup;

This control assembly is exported a low level signal in one second time period, to make this second converting member effect; And

This second converting member is one second high-frequency and high-voltage power supply with the direct current voltage transitions that this bus power source provided, keep the state that can scan for these white-light emitting parts, wherein, the power that this bus power source of this second time period provides is the power that this bus power source less than this very first time section provides

Wherein, this first converting member is an inverter; With

Wherein, this second converting member is an inverter.

8. method as claimed in claim 7, wherein these white-light emitting parts are cold-cathode tubes.

9. method as claimed in claim 7, wherein these white-light emitting parts are discharge lamps.

10. method as claimed in claim 7, wherein this control assembly is an application-specific integrated circuit (ASIC).

11. the method for a management bus power supply, be to use in one with charge coupled device in the scanner of its photo-sensitive cell, this scanner has a control assembly, a converting member and white-light emitting parts, this method comprises:

USB interface by main frame provides this bus power source in this scanner;

This control assembly is exported a signal in a very first time section, to make this converting member effect;

This converting member is one first high-frequency and high-voltage power supply with the direct current voltage transitions that this bus power source provided, for the usefulness of this white-light emitting parts startup;

This control assembly is exported a pulse-width signal in one second time period, to make this converting member effect; And

This converting member is one second high-frequency and high-voltage power supply with the direct current voltage transitions that this bus power source provided, keep the state that can scan for these white-light emitting parts, wherein, the power that this bus power source of this second time period provides be the power that provides of this bus power source less than this very first time section and

Wherein, converting member is an inverter.

12. method as claimed in claim 11, wherein, these white-light emitting parts are cold-cathode tubes.

13. method as claimed in claim 11, wherein, these white-light emitting parts are discharge lamps.

14. method as claimed in claim 11, wherein, this control assembly is an application-specific integrated circuit (ASIC).

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