公开(公告)号：JPH07231133A

公开(公告)日：1995-08-29

申请号：JP4519694

申请日：1994-02-18

Applicant: CANON KK

Inventor： NITTA ATSUSHI

IPC: H01S5/00 ,  H01S5/042 ,  H01S5/06 ,  H01S5/0625 ,  H01S5/343 ,  H01S3/103 ,  H01S3/18

Abstract: PURPOSE:To change polarized condition of an output beam by an external control. CONSTITUTION:A semiconductor laser for polarized modulation has active layer formed of two or more active regions 31, 32 haying different gain spectrum within one resonator, at least one active region 32 of the active layer has a gain for TM polarization which is larger than that for the TE polarization and at least the other active region 31 of the active layer has a gain for TE polarization which is larger than that for the TM polarization.

公开(公告)号：JPH07226563A

公开(公告)日：1995-08-22

申请号：JP1706694

申请日：1994-02-14

Applicant: HITACHI LTD

Inventor： AOKI MASAHIRO ,  TANIWATARI TAKESHI ,  SUZUKI MAKOTO ,  TSUTSUI TAKAYUKI

IPC: C23C16/18 ,  G02F1/025 ,  H01L21/205 ,  H01L27/15 ,  H01L29/06 ,  H01S3/23 ,  H01S5/00 ,  H01S5/022 ,  H01S5/026 ,  H01S5/0625 ,  H01S5/12 ,  H01S5/125 ,  H01S5/20 ,  H01S5/227 ,  H01S5/343 ,  H01S5/40 ,  H01S3/18 ,  H01S3/25

Abstract: PURPOSE:To form distributed feedback type lasers and distributed reflection type lasers on the same substrate by a simple forming method which lasers have uniform static characteristics and dynamic characteristics and are different in oscillation wavelength. CONSTITUTION:A plurality of pairs of stripe type insulating masks 2 wherein gaps of constant width Wg are formed are formed at the positions where laser optical waveguides are to be formed on a semiconductor substrate 1. By organic metal vapor growth, optical waveguide layers 3, 4, 5 for semiconductor lasers are crystal-grown. A plurality of pairs of stripe type dimensions Wm are mutually different. A plurality of distributed feedback type semiconductor lasers 7-l, 7-2,...7-n which are different in the thickness and the composition of an optical waveguide and the oscillation wavelength are formed on the same substrate 1. A plurality of distributed feedback type lasers and distributed reflection type lasers which have uniform static characteristics and dynamic characteristics and are different in oscillation wavelength are formed on the same substrate by a very simple forming method. Element performance and yield are remarkably improved.

公开(公告)号：JPH07202342A

公开(公告)日：1995-08-04

申请号：JP35070393

申请日：1993-12-28

Applicant: ANRITSU CORP

Inventor： YOSHIDAYA HIROAKI

IPC: H01L33/06 ,  H01L33/20 ,  H01L33/30 ,  H01S5/00 ,  H01S5/0625 ,  H01S3/18 ,  H01L33/00

Abstract: PURPOSE:To control the polarization of laser beams emitted from nearly the same region in a single element. CONSTITUTION:In the element with a single semiconductor substrate 1, a clad layer 2. a quantum well layer 3, and a current-injection means for injecting current to the quantum well layer, a first well layer 5 where a quantum well layer radiates TE mode and a second quantum well layer 6 for radiating TM mode are included. the light in TE mode and that in TM mode controlled by current injected by the current injection means is emitted from nearly the same region.

公开(公告)号：JPH07202330A

公开(公告)日：1995-08-04

申请号：JP33512794

申请日：1994-12-21

Applicant: AMERICAN TELEPHONE & TELEGRAPH

Inventor： TEINNHENGU CHIU ,  MAIKERU DEII UIRIAMUZU

IPC: H01S5/00 ,  H01S5/042 ,  H01S5/0625 ,  H01S5/10 ,  H01S5/12 ,  H01S5/125 ,  H01S3/18

Abstract: PURPOSE: To extend life time of an element and improve yield by forming a clad layer in a grating formation region formed by etching, and depositing a conductive material layer in a mode for grating over it. CONSTITUTION: On the surface of a III-V semiconductor substrate 11 which is semiinsulating or doped, a first n-type contact point layer 12, a wavelength layer 13, a second n-type contact point layer 14 and an active layer 15 are deposited in this order. Then, in the region of the substrate 11 where a grating 17 is formed, the active layer 15 is selectively etched up to above the waveguide layer 13, and a clad layer 16 is grown on the region for forming the grating 17. Then, a photoresist is deposited on the structure thus obtained and then patterned. Then by photolithography technology, a conductive material layer is deposited on the clad layer 16 in the form of the grating 17. Thus, life time of an element is extended, and yield is improved without raising the processing cost.

公开(公告)号：JPH07193541A

公开(公告)日：1995-07-28

申请号：JP29202394

申请日：1994-11-02

Applicant: AMERICAN TELEPHONE & TELEGRAPH

Inventor： TOOMASU ERU KOTSUHO ,  KOYAMA FUMIO ,  KANNII RIYUU

IPC: G02F1/01 ,  G02F1/025 ,  H01L27/15 ,  H01S3/00 ,  H01S5/026 ,  H01S5/0625 ,  H01S5/50 ,  H04B10/04 ,  H04B10/06 ,  H04B10/142 ,  H04B10/152

Abstract: PURPOSE: To provide the method and device which use two or more optical modulators to insulate an optical signal source. CONSTITUTION: This device generates an open gate array which transmits a forward data signal and attenuates a reverse shoal and is times to be synchronous with the data signal. In another embodiment, a reflected optical signal is mainly attenuated by using a passive waveguide and optical modulators 2 and 3. This passive waveguide gives a propagation delay so that the signal reflected from its end face is attenuated by optical modulators 2 and 3. This device is suitable for the use as an optical isolator to a light source in a high speed optical fiber data transmission system.

公开(公告)号：JPH0789131A

公开(公告)日：1995-04-04

申请号：JP23781993

申请日：1993-09-24

Applicant: HITACHI LTD ,  HITACHI KOKI KK

Inventor： SAITO SUSUMU ,  KATAOKA KEIJI ,  NAKATSUKA SHINICHI ,  YANO SHINICHIRO ,  ARIMOTO AKIRA

IPC: B41J2/44 ,  G02B26/10 ,  G02B26/12 ,  H01S5/062 ,  H01S5/0625 ,  H04N1/40

Abstract: PURPOSE:To embody an optical system capable of continuously changing the dimension of a printing dot at a high speed. CONSTITUTION:The semiconductor laser 10 of a beam source is constituted by forming a beam diameter control part 12 on a single semiconductor crystal other than a laser beam emission control part 11 functioning as a usual semiconductor laser and the diameter of laser beam is modulated along with laser output corresponding to an image signal and an image is written on a scanning surface 40 through a polygon mirror 20 and a scanning lens 30.

公开(公告)号：JPH0722215B2

公开(公告)日：1995-03-08

申请号：JP17267385

申请日：1985-08-05

IPC: H01S5/00 ,  H01S5/042 ,  H01S5/0625 ,  H01S5/12 ,  H01S3/18

公开(公告)号：JPH0715068A

公开(公告)日：1995-01-17

申请号：JP15394393

申请日：1993-06-24

Applicant: NIPPON TELEGRAPH & TELEPHONE

Inventor： ISHIDA OSAMU ,  TADA YASUHIKO ,  ISHII HIROYUKI

IPC: H01S5/042 ,  H01S5/0625 ,  H01S3/096

Abstract: PURPOSE:To provide multi-electrode semiconductor laser driver in which the impedance matching is sustained while allowing modulation of current containing a DC component even when the current branch ratio is regulated and in which a large margin can be ensured when the oscillation frequency is regulated to be swept continuously at the time of driving a multi-electrode semiconductor DBR. CONSTITUTION:When a semiconductor laser comprising a plurality of current injection electrodes 901-90M is fed with current containing a DC component, while being branched, from a current supply means 10, at least one current branched by a current branching means 20 is attenuated by a current attenuating means 301-30k and the current branch conditions for the electrodes 901-90M are regulated by varying the attenuation.

公开(公告)号：JPH06291403A

公开(公告)日：1994-10-18

申请号：JP31562992

申请日：1992-11-02

Applicant: AMERICAN TELEPHONE & TELEGRAPH

Inventor： TOOMASU ERU KOTSUKU ,  SHIERIRU ERU UTSUDOWAADO

IPC: H01S5/042 ,  H01S5/026 ,  H01S5/0625 ,  H01S5/068 ,  H01S5/0687 ,  H04B10/155 ,  H01S3/133 ,  H01S3/096

Abstract: PURPOSE: To realize wavelength division multiplexing while sustaining the single longitudinal mode operation of laser by employing a distributed Bragg reflector laser, and an optical emitter having a mode stabilization feedback means. CONSTITUTION: Output power from a Bragg section 10 is detected by an integrated photodiode 14 and a signal therefrom is applied directly to a lock-in amplifier element 20. An amplifier 22 amplifies a detected signal and feeds back the output to the Bragg section of laser thus closing the feedback loop. A feedback means comprises the lock-in amplifier element 20, the amplifier 22 and an oscillator 21. This arrangement can sustain the single longitudinal mode operation of laser.

公开(公告)号：JPH06252475A

公开(公告)日：1994-09-09

申请号：JP4065894

申请日：1994-02-16

Applicant: AMERICAN TELEPHONE & TELEGRAPH

Inventor： SHII DORAGON ,  AI PII KAMINOU

IPC: H01S3/082 ,  H01S3/05 ,  H01S3/10 ,  H01S5/00 ,  H01S5/026 ,  H01S5/06 ,  H01S5/0625 ,  H01S5/10 ,  H01S5/40 ,  H01S5/50 ,  H04Q11/00 ,  H01S3/18

Abstract: PURPOSE: To provide a high speed tuning laser which can take out a desired frequency through the use of an optical integrated circuit supplying a wide gain band by forming a laser cavity in a semiconductor wafer and forming a frequency routing device in the cavity. CONSTITUTION: One regulated N×N frequency routing device 12 is used between two reflecting surfaces 20 and 24 on the semiconductor wafer 10. Waveguides 1 and 16 connected to the device 12 have integrated optical amplifiers 18 and 22 which selectively operate as gates. They selectively operate as gates for suppressing the flow of the light energy of the waveguides 14 and 16 or as gain supply elements amplifying the flow of light energy of the waveguides 14 and 16. One selected optical amplifier 18 or 22 is activated by bias current and it laser-operates in a prescribed path between the reflecting surfaces 20 and 24. A laser operation is maintained to the prescribed frequency in the path and the laser can be tuned at high speed.