Pn junction optical modulating device having a buffer layer with small
energy gap
    1.
    发明授权
    Pn junction optical modulating device having a buffer layer with small energy gap 失效
    具有具有小能隙的缓冲层的Pn结光调制装置

    公开(公告)号:US4991921A

    公开(公告)日:1991-02-12

    申请号:US442521

    申请日:1989-11-27

    IPC分类号: G02F1/015 G02F1/025

    CPC分类号: G02F1/025 G02F2001/0157

    摘要: An optical modulating device is disclosed which has, on a substrate directly or via a lower cladding layer, an optical waveguide layer, an upper cladding layer of a refractive index smaller than that of the optical waveguide layer and a pair of electrodes for applying an electric field across the substrate and the upper cladding layer and in which the absorption coefficient for incident light of a fixed intensity incident to the optical waveguide layer is varied by the electric field applied across the pair of electrodes to perform the modulation of the light and the modulated light is emitted from a light emitting end face of the optical waveguide layer. In accordance with the present invention, a pn junction is formed in the upper cladding layer and at least one buffer layer of an energy gap smaller than that of the upper cladding layer but larger than that of the optical waveguide layer is interposed between the upper cladding layer and the optical waveguide layer.

    摘要翻译: 公开了一种光学调制装置,其在衬底上直接或经由下包层,光波导层,折射率小于光波导层的折射率的上包层和用于施加电的一对电极 并且其中入射到光波导层的固定强度的入射光的吸收系数由施加在该对电极上的电场而变化,以执行光的调制和被调制的 光从光波导层的发光端面发射。 根据本发明,在上部包层中形成pn结,并且至少一个能量间隙的缓冲层比上部包覆层的能隙小,但是比光波导层大的缓冲层插入在上部包层 层和光波导层。

    Optical modulation device
    2.
    发明授权
    Optical modulation device 失效
    光调制装置

    公开(公告)号:US4913506A

    公开(公告)日:1990-04-03

    申请号:US311218

    申请日:1989-02-16

    摘要: An optical modulation device is disclosed in which a difference between the photon energy of incident light and the band-gap energy of the modulation waveguide layer is set to a value greater than 50 meV to thereby suppress the degradation of the modulation voltage and the modulation band width which is caused by an increase in the intensity of incident light and in that the optical modulation device is formed in a predetermined length to thereby decrease the modulation voltage. The energy gap of the optical waveguide layer of the optical modulation device is varied continuously or discontinuously in the direction of its thickness to provide a constant absorption coefficient thickwise of the optical waveguide layer so that the electric field intensity distribution in the optical waveguide layer is compensated for, by which overlap of the light distribution and the absorption coefficient is increased so as to decrease the modulation voltage and broaden the modulation band by the reduction of the length of the device. The composition, thickness and stripe width of the optical waveguide layer are changed so that its absorption coefficient increases from the light receiving end face of the optical waveguide layer toward its light emitting end face, thereby making the number of carriers absorbed per unit length substantially constant in the direction of travel of light.

    摘要翻译: 公开了一种光调制装置,其中将入射光的光子能量与调制波导层的带隙能量之间的差设定为大于50meV的值,从而抑制调制电压和调制带的劣化 由入射光强度的增加引起的宽度,并且光调制装置形成为预定长度,从而降低调制电压。 光调制装置的光波导层的能隙在其厚度方向上连续或不连续地变化,以提供光波导层厚度的恒定吸收系数,使得光波导层中的电场强度分布得到补偿 由此,增加了光分布和吸收系数的重叠,从而降低了调制电压,并且通过减小器件的长度来扩大调制频带。 改变光波导层的组成,厚度和条纹宽度,使得其吸收系数从光波导层的光接收端面向其发光端面增加,从而使每单位长度吸收的载流子基本恒定 在光的行进方向。

    Optical modulation element
    3.
    发明授权
    Optical modulation element 失效
    光调制元件

    公开(公告)号:US4946243A

    公开(公告)日:1990-08-07

    申请号:US387511

    申请日:1989-07-28

    CPC分类号: G02F1/025 G02F2001/0157

    摘要: An optical modulation element is disclosed which has, on a substrate directly or through a lower clad layer, an optical waveguide layer of a low impurity concentration, an upper clad layer of a refractive index smaller than that of the optical waveguide layer, and electrodes, and in which light of a constant intensity incident on a light incident end face of the optical waveguide layer is intensity-modulated by changing the absorption coefficient of the optical waveguide layer by means of an electric field applied thereto across the electrodes so that the thus modulated light is emitted from a light emitting end face of the optical waveguide layer. In accordance with the present invention, a plurality of low impurity concentration regions and a plurality of high impurity concentration regions are disposed alternately with each other in contact with at least one of the lower and upper clad layers in the direction of travel of light in such a manner that the distribution density of the plurality of high impurity concentration regions increases in the direction of travel of light.

    Optical communication system and optical transmitting device
    5.
    发明授权
    Optical communication system and optical transmitting device 失效
    光通信系统和光传输设备

    公开(公告)号:US5786918A

    公开(公告)日:1998-07-28

    申请号:US575174

    申请日:1995-12-19

    CPC分类号: H04B10/25077 H04J14/08

    摘要: An optical communication system of a construction wherein the average wavelength dispersion value of the transmission optical fiber used, the optical output intensity of each optical amplifier repeater inserted in the transmission optical fiber and the widths of return-to-zero optical pulses transmitted over the transmission line are determined so as to compensate for the pulse compression effect by the nonlinear optical effect produced on the optical pulses by the pulse spreading effect by the wavelength dispersion effect. An optical multiplexer in the optical transmitting device time-division multiplexes the return-to-zero optical pulses, and the optical multiplexed signal is provided as an alternating-amplitude optical signal with the amplitudes of the return-to-zero optical pulses alternated.

    摘要翻译: 一种结构的光通信系统,其中使用的传输光纤的平均波长色散值,插入在传输光纤中的每个光放大器中继器的光输出强度以及通过传输传输的归零光脉冲的宽度 线被确定为通过由脉冲扩散效应通过波长色散效应在光脉冲上产生的非线性光学效应来补偿脉冲压缩效应。 光发射装置中的光复用器对归零光脉冲进行时分复用,并且光复用信号被提供为交替振幅的光信号,并且返回到零的光脉冲的幅度交替。

    Multi-layered semi-conductor photodetector
    8.
    发明授权
    Multi-layered semi-conductor photodetector 失效
    多层半导体光电探测器

    公开(公告)号:US4682196A

    公开(公告)日:1987-07-21

    申请号:US806746

    申请日:1985-12-09

    摘要: A semiconductor device, which is formed by a sequential lamination of a first semiconductor layer having a carrier concentration more than 10.sup.17 cm.sup.-3, a second semiconductor layer having a carrier concentration less than 10.sup.16 cm.sup.-3, a third semiconductor layer having a carrier concentration more than 10.sup.17 cm.sup.-3 and a thickness less than 300 .ANG., a fourth semiconductor layer having a carrier concentration less than 10.sup.16 cm.sup.-3, and a fifth semiconductor layer having a carrier concentration more than 10.sup.17 cm.sup.-3 and, in which the first and fifth semiconductor layers are the same in conductivity type and the third semiconductor layer is different in conductivity type from the fifth semiconductor layer. In accordance with the present invention, the energy gap of the third semiconductor layer is larger than the energy gaps of the second and fourth semiconductor layers. An annular region of a semi-insulating material or of the same conductivity type as that of the third semiconductor layer may be formed around an active region to extend from the fifth semiconductor layer to the second semiconductor layer.

    摘要翻译: 一种半导体器件,其通过顺次层叠具有载流子浓度大于1017cm -3的第一半导体层,载流子浓度小于1016cm-3的第二半导体层,具有载流子浓度的第三半导体层 大于1017cm-3,厚度小于300,载流子浓度小于1016cm-3的第四半导体层和载流子浓度大于1017cm-3的第五半导体层,其中第一 并且第五半导体层的导电类型相同,并且第三半导体层的导电类型与第五半导体层不同。 根据本发明,第三半导体层的能隙大于第二和第四半导体层的能隙。 可以在有源区周围形成半绝缘材料或与第三半导体层相同的导电类型的环形区域,以从第五半导体层延伸到第二半导体层。

    Method for manufacturing diffraction grating
    9.
    发明授权
    Method for manufacturing diffraction grating 失效
    衍射光栅的制造方法

    公开(公告)号:US4660934A

    公开(公告)日:1987-04-28

    申请号:US710984

    申请日:1985-03-12

    IPC分类号: G02B5/18 G03F7/00 G03F7/095

    摘要: A method for manufacturing diffraction grating, in which after forming, on a substrate, one of a negative type photoresist film (an N film) and a positive type photoresist film (a P film) to cover a first region A and the other of the negative type photoresist film and the positive type photoresist film, or the latter film on the former one to cover a second region B, the first region and the second region are subjected to two-beam interference exposure, thereby forming a diffraction grating in which corrugations in the first region and the second region are reverse in phase to each other, through utilization of characteristics of the negative type photoresist film and the positive type photoresist film. Another feature of the present invention resides in that after forming, on a substrate, a structure in which a negative type photoresist film (an N film) is formed to cover only a first region A and the negative type photoresist film is formed on a positive type photoresist film (a P film) to cover a second region B, the first region and the second region of the substrate are subjected to two-beam interference exposure, thereby forming a diffraction grating in which corrugations in the first region and the second region are reverse in phase to each other, through utilization of characteristics of the negative type photoresist film and the positive type photoresist film.

    摘要翻译: 制造衍射光栅的方法,其中在基板上形成负型光致抗蚀剂膜(N膜)和正型光致抗蚀剂膜(P膜)之一以覆盖第一区域A和另一个 负型光致抗蚀剂膜和正型光致抗蚀剂膜,或者在前者的后者膜覆盖第二区域B,第一区域和第二区域受到双光束干涉曝光,从而形成衍射光栅,其中波纹 通过利用负型光致抗蚀剂膜和正型光致抗蚀剂膜的特性,在第一区域和第二区域中的相位彼此相反。 本发明的另一个特征在于,在基板上形成后,形成负型光致抗蚀剂膜(N膜)仅覆盖第一区域A并且负型光致抗蚀剂膜形成为阳性的结构 (P膜)覆盖第二区域B,对基板的第一区域和第二区域进行双光束干涉曝光,从而形成衍射光栅,其中第一区域和第二区域中的波纹 通过利用负型光致抗蚀剂膜和正型光致抗蚀剂膜的特性,彼此相反。