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WO1998002719A1 - Dispositif et procede de constitution d'un paquet optique en vue d'une retroaction - Google Patents

Dispositif et procede de constitution d'un paquet optique en vue d'une retroaction Download PDF

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Publication number
WO1998002719A1
WO1998002719A1 PCT/US1997/012023 US9712023W WO9802719A1 WO 1998002719 A1 WO1998002719 A1 WO 1998002719A1 US 9712023 W US9712023 W US 9712023W WO 9802719 A1 WO9802719 A1 WO 9802719A1
Authority
WO
WIPO (PCT)
Prior art keywords
optical
predetermined portion
partially reflective
optical element
feedback
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US1997/012023
Other languages
English (en)
Inventor
Jang-Hun Yeh, (James)
Austin V. Harton
Wenbin Jiang
Michael Lebby
Daniel M. Lurey
James J. Morikuni
Karl Wyatt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Motorola Solutions Inc
Original Assignee
Motorola Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Motorola Inc filed Critical Motorola Inc
Priority to JP10506144A priority Critical patent/JPH11513198A/ja
Priority to EP97934097A priority patent/EP0859947A4/fr
Publication of WO1998002719A1 publication Critical patent/WO1998002719A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10544—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation by scanning of the records by radiation in the optical part of the electromagnetic spectrum
    • G06K7/10821—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation by scanning of the records by radiation in the optical part of the electromagnetic spectrum further details of bar or optical code scanning devices
    • G06K7/10851—Circuits for pulse shaping, amplifying, eliminating noise signals, checking the function of the sensing device
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
    • G01J1/00—Photometry, e.g. photographic exposure meter
    • G01J1/10—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void
    • G01J1/20—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void intensity of the measured or reference value being varied to equalise their effects at the detectors, e.g. by varying incidence angle
    • G01J1/28—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void intensity of the measured or reference value being varied to equalise their effects at the detectors, e.g. by varying incidence angle using variation of intensity or distance of source
    • G01J1/30—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void intensity of the measured or reference value being varied to equalise their effects at the detectors, e.g. by varying incidence angle using variation of intensity or distance of source using electric radiation detectors
    • G01J1/32—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void intensity of the measured or reference value being varied to equalise their effects at the detectors, e.g. by varying incidence angle using variation of intensity or distance of source using electric radiation detectors adapted for automatic variation of the measured or reference value
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/10—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation
    • G06K7/10544—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation by scanning of the records by radiation in the optical part of the electromagnetic spectrum
    • G06K7/10821—Methods or arrangements for sensing record carriers, e.g. for reading patterns by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation by scanning of the records by radiation in the optical part of the electromagnetic spectrum further details of bar or optical code scanning devices
    • G06K7/10831—Arrangement of optical elements, e.g. lenses, mirrors, prisms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/10—Construction or shape of the optical resonator, e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region
    • H01S5/18—Surface-emitting [SE] lasers, e.g. having both horizontal and vertical cavities
    • H01S5/183—Surface-emitting [SE] lasers, e.g. having both horizontal and vertical cavities having only vertical cavities, e.g. vertical cavity surface-emitting lasers [VCSEL]
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K2207/00—Other aspects
    • G06K2207/1015—Hologram
    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K2207/00—Other aspects
    • G06K2207/1018—Source control
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/022—Mountings; Housings
    • H01S5/02208—Mountings; Housings characterised by the shape of the housings
    • H01S5/02212—Can-type, e.g. TO-CAN housings with emission along or parallel to symmetry axis
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/022—Mountings; Housings
    • H01S5/0225—Out-coupling of light
    • H01S5/02257—Out-coupling of light using windows, e.g. specially adapted for back-reflecting light to a detector inside the housing
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/02—Structural details or components not essential to laser action
    • H01S5/026—Monolithically integrated components, e.g. waveguides, monitoring photo-detectors, drivers
    • H01S5/0262—Photo-diodes, e.g. transceiver devices, bidirectional devices
    • H01S5/0264—Photo-diodes, e.g. transceiver devices, bidirectional devices for monitoring the laser-output
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/06—Arrangements for controlling the laser output parameters, e.g. by operating on the active medium
    • H01S5/068—Stabilisation of laser output parameters
    • H01S5/0683—Stabilisation of laser output parameters by monitoring the optical output parameters

Definitions

  • the present invention relates to providing optical feedback for applications requiring optical emitters and, more particularly, to using holograms as a feedback mechanism.
  • the present invention relates, in general to a vertical cavity surface emitting laser (VCSEL).
  • VCSEL vertical cavity surface emitting laser
  • a VCSEL is a semiconductor laser diode in which the laser oscillation and the optical emission occur in a direction normal to the pn junction plane. This device has many properties which are advantageous when compared to the more commonly used edge-emitting laser diodes. These properties include: low optical beam divergence, a circular optical output, and single longitudinal mode operation. In addition, VCSEL devices are manufactured in a manner which allows wafer level testing of individual devices. These properties make
  • VCSELs attractive in applications such as optical data storage, data communication and laser scanners.
  • dynamic stabilization and control of the optical output power is required.
  • edge emitting laser diodes this is usually accomplished by allowing a portion of the light emitted by the laser diode, i.e., using light emitted from the laser diode's rear mirror for bias control, to illuminate an optical photodetector which produces a photocurrent proportional to the intensity of the light emitted by the laser diode.
  • This optically generated photocurrent drives a feedback circuit which controls the laser bias current.
  • Due to the structure of the VCSEL light emitted from the rear mirror is absorbed by the GaAs substrate. Thus, the system of using light emitted fom the rear mirror is unavailable fo bias control.
  • FIG. 1 is a graphic representation of one embodiment of steps of a method in accordance with the present invention.
  • FIG. 2 is a flow chart showing one embodiment of a device in accordance with the present invention.
  • FIG. 3 is a schematic representation of one embodiment of a device in accordance with the invention.
  • the present invention provides a feedback mechanism for automatic power control for an optical emitter, thus providing automatic adjustment of electrical input current for the optical emitter.
  • This method improves the power stability of semiconductor laser diodes.
  • the utilization of the feedback mechanism provides the advantage that the whole package containing the holographic optical element adapts the optical emitter without significant mechanical modification.
  • the feedback current may be controlled by the diffraction efficiency of the holographic optical element because the reflecting power is determined by the design of the holographic optical element.
  • the design includes the index modulation amplitude, thickness, and grating structure of the holographic film.
  • the use of the holographic optical element allows control of the size of a beam sent to the optical sensing element, thus allowing one to choose a smaller detector than was possible with the prior art.
  • the present invention uses a hologram to direct a predetermined portion of the light emitted from the top surface of the VCSEL onto a separate adjacent photodetector.
  • the resulting photocurrent is proportional to the total optical power of the VCSEL.
  • the hologram can be designed to reflect a predetermined percentage of the total optical output power.
  • the use of the hologram can also be used to reduce the area of illumination on the optical sensing element. This may result in a reduction in the size of the required photodetector.
  • FIG. 1 numeral 100, is a graphic representation of one embodiment of steps of a method in accordance with the present invention. The method provides optical feedback for an optical package.
  • the method includes the steps of: A) generating a beam of light using an optical emitter responsive to an electrical input current (102); B) directing a first predetermined portion of the beam, using a partially reflective holographic optical element/reflector, to exit the partially reflective holographic optical element/reflector and to diffract a second predetermined portion of the beam to an optical sensing unit (104); C) generating feedback for adjusting the electrical input current to the optical emitter based on a received optical power of the second predetermined portion of the beam using an optical sensing unit that is arranged to receive the second predetermined portion of the beam (106).
  • the partially reflective holographic optical element/reflector may be selected to be one of: A) a partially reflective volume holographic optical element recorded in a holographic film; B) a diffractive optical element other than a partially reflective volume holographic optical element; and C) a partially reflecting surface tilted at a predetermined angle.
  • the optical emitter is typically one of: A) an edge emitting laser; B) a vertical cavity surface-emitting laser; and C) a light-emitting diode.
  • the optical sensing unit is generally at least a photodetector.
  • FIG. 2, numeral 200, is a flow chart showing one embodiment of a device in accordance with the present invention.
  • the device for an optical package provides optical feedback and includes an optical emitter (202), a partially reflective holographic optical element or reflector (204), and an optical sensing unit (206).
  • the optical emitter (202) is responsive to an electrical input current, and generates a beam of light.
  • the partially reflective holographic optical element/reflector (204) is arranged to allow a first predetermined portion of the beam to exit the partially reflective holographic optical element/reflector and to diffract a second predetermined portion of the beam to an optical sensing unit (206).
  • the optical sensing unit (206) is arranged to receive the second predetermined portion of the beam, for generating feedback for adjusting the electrical input current to the optical emitter based on a received optical power of the second predetermined portion of the beam.
  • the optical sensing unit (206) provides the feedback current to a current control unit (208) that inputs en electrical input current to the optical emitter (202).
  • the partially reflective holographic optical element/reflector (202) is typically one of: A) a partially reflective volume holographic optical element recorded in a holographic film; B) a diffractive optical element other than a partially reflective volume holographic optical element; and C) a partially reflecting surface tilted at a predetermined angle.
  • the optical emitter (204) is generally one of: A) an edge emitting laser; B) a vertical cavity surface- emitting laser; and C) a light-emitting diode.
  • a photo detector is often utilized as the optical sensing unit (206).
  • An optical storage unit may utilize the device of the present invention.
  • Typical optical storage units are: a compact disk player; a digital video disk player; a compact disk read- only memory drive; a magneto-optical disk drive; and a laser disk player.
  • FIG. 3 is a schematic representation of one embodiment of a device in accordance with the invention.
  • the device is typically an enclosed unit having an optical emitter (302), a partially reflective holographic optical element or reflector (304) for partialy reflecting the laser beam to an optical sensing unit (306) and allowing transmittal of another predetermined portion of the laser beam outside the enclosed unit.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Theoretical Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Artificial Intelligence (AREA)
  • Optics & Photonics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Semiconductor Lasers (AREA)
  • Photometry And Measurement Of Optical Pulse Characteristics (AREA)
  • Led Device Packages (AREA)

Abstract

L'invention porte sur un dispositif (200, 300) et sur un procédé (100) de rétroaction optique d'un paquet optique. Le dispositif comporte: un émetteur optique (202) répondant à l'introduction d'un courant électrique (208) pour produire un faisceau lumineux; un élément optique holographique partiellement réfléchissant/réflecteur (204) conçu pour permettre la sortie d'une première partie prédéterminée du faisceau de l'élément optique holographique partiellement réfléchissant/réflecteur, et la diffraction d'une deuxième partie prédéterminée du faisceau vers un détecteur optique (206); et le détecteur optique conçu pour recevoir la deuxième partie prédéterminée du faisceau de manière à produire une rétroaction servant à ajuster le courant électrique introduit dans l'émetteur optique sur la base de la puissance optique de la deuxième partie prédéterminée du faisceau.
PCT/US1997/012023 1996-07-16 1997-07-11 Dispositif et procede de constitution d'un paquet optique en vue d'une retroaction Ceased WO1998002719A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP10506144A JPH11513198A (ja) 1996-07-16 1997-07-11 ホログラムを使用した光学的エミッタのための光学的フィードバックを提供する装置、方法、バーコード・スキャナおよび光学的記憶ユニット
EP97934097A EP0859947A4 (fr) 1996-07-16 1997-07-11 Dispositif et procede de constitution d'un paquet optique en vue d'une retroaction

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US68297396A 1996-07-16 1996-07-16
US08/682,973 1996-07-16

Publications (1)

Publication Number Publication Date
WO1998002719A1 true WO1998002719A1 (fr) 1998-01-22

Family

ID=24742024

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1997/012023 Ceased WO1998002719A1 (fr) 1996-07-16 1997-07-11 Dispositif et procede de constitution d'un paquet optique en vue d'une retroaction

Country Status (7)

Country Link
EP (1) EP0859947A4 (fr)
JP (1) JPH11513198A (fr)
KR (1) KR19990044693A (fr)
CN (1) CN1197510A (fr)
CA (1) CA2230811A1 (fr)
TW (1) TW486846B (fr)
WO (1) WO1998002719A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2374142A (en) * 2000-12-15 2002-10-09 Agilent Technologies Inc Optical monitoring systems
EP1047970A4 (fr) * 1998-08-31 2006-03-22 Digital Optics Corp Controleur de puissance et systeme a diffraction pour laser a cavite verticale et a emission par la surface
US8611382B2 (en) 2009-02-25 2013-12-17 Koninklijke Philips N.V. Output power stabilization for laser diodes using the photon-cooling dependent laser voltage
US11769984B2 (en) 2021-07-30 2023-09-26 Panasonic Holdings Corporation Laser module, laser oscillator and laser processing system

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0000209D0 (en) * 2000-01-07 2000-03-01 Holmetrica Limited Holographic multiplexed image sensor
JP4915310B2 (ja) * 2007-08-06 2012-04-11 株式会社デンソーウェーブ 光学的情報読取装置
CN102646925B (zh) * 2012-04-25 2016-02-24 青岛镭创光电技术有限公司 带光反馈激光模组结构

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3949233A (en) * 1974-08-15 1976-04-06 Pitney-Bowes, Inc. Hand held bar code reader with constant linear amplifier output
US5122644A (en) * 1988-11-17 1992-06-16 Alps Electric Co., Ltd. Optical code reading device with autofocussing
US5475210A (en) * 1991-09-09 1995-12-12 Kabushiki Kaisha Toshiba Noise reduction system for optical record and reproduction apparatus using auto-power controlled semiconductor laser device
US5612529A (en) * 1994-10-31 1997-03-18 Psc Inc. System for bar code reading and scanning with automatic gain control

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6086887A (ja) * 1983-10-19 1985-05-16 Matsushita Electric Ind Co Ltd 半導体レ−ザ装置
EP0605929B1 (fr) * 1993-01-04 1998-07-29 Koninklijke Philips Electronics N.V. Dispositif pour balayer optiquement une surface
KR100269710B1 (ko) * 1996-01-23 2000-10-16 윤종용 광출력장치 및 이를 채용한 광픽업장치

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3949233A (en) * 1974-08-15 1976-04-06 Pitney-Bowes, Inc. Hand held bar code reader with constant linear amplifier output
US5122644A (en) * 1988-11-17 1992-06-16 Alps Electric Co., Ltd. Optical code reading device with autofocussing
US5475210A (en) * 1991-09-09 1995-12-12 Kabushiki Kaisha Toshiba Noise reduction system for optical record and reproduction apparatus using auto-power controlled semiconductor laser device
US5612529A (en) * 1994-10-31 1997-03-18 Psc Inc. System for bar code reading and scanning with automatic gain control

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP0859947A4 *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1047970A4 (fr) * 1998-08-31 2006-03-22 Digital Optics Corp Controleur de puissance et systeme a diffraction pour laser a cavite verticale et a emission par la surface
JP2011009782A (ja) * 1998-08-31 2011-01-13 Digital Optics Corp 垂直共振器面発光レーザのための回折性パワーモニタ
GB2374142A (en) * 2000-12-15 2002-10-09 Agilent Technologies Inc Optical monitoring systems
GB2374142B (en) * 2000-12-15 2004-09-08 Agilent Technologies Inc Optical monitoring systems
US8611382B2 (en) 2009-02-25 2013-12-17 Koninklijke Philips N.V. Output power stabilization for laser diodes using the photon-cooling dependent laser voltage
US11769984B2 (en) 2021-07-30 2023-09-26 Panasonic Holdings Corporation Laser module, laser oscillator and laser processing system

Also Published As

Publication number Publication date
EP0859947A4 (fr) 2000-04-05
CA2230811A1 (fr) 1998-01-22
EP0859947A1 (fr) 1998-08-26
KR19990044693A (ko) 1999-06-25
CN1197510A (zh) 1998-10-28
TW486846B (en) 2002-05-11
JPH11513198A (ja) 1999-11-09

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