公开(公告)号：US20230056455A1

公开(公告)日：2023-02-23

申请号：US17842977

申请日：2022-06-17

Applicant: FUJITSU OPTICAL COMPONENTS LIMITED

Inventor： Akira OKA

IPC: G02B6/125

Abstract: A waveguide element includes a first waveguide and a second waveguide. The first waveguide includes a first main rib and a first slab that has a smaller thickness than that of the first main rib and in which a slab mode of light propagates. The second waveguide includes a second main rib that is optically coupled with the first main rib and in which the light propagates, a second slab that has a smaller thickness than that of the second main rib, that is optically coupled with the first slab, and in which the slab mode propagates, and a side rib that has a larger thickness than that of the second slab. The slab mode that propagates through the second slab transitions to the side rib in accordance with travel of the light that propagates in the first main rib and the second main rib.

公开(公告)号：US11495589B2

公开(公告)日：2022-11-08

申请号：US16806256

申请日：2020-03-02

Applicant: FUJITSU OPTICAL COMPONENTS LIMITED

Inventor： Kento Takahashi ,  Teruhiro Kubo ,  Hiroshi Kobayashi

IPC: H01L25/16 ,  H01L23/00 ,  H01L23/31 ,  H01L23/498 ,  H01L23/66 ,  H01P11/00 ,  H01L21/48 ,  H01L21/56 ,  H01P3/00

Abstract: An optical module includes an optical semiconductor chip including a first electrode pad, a second electrode pad, and a third electrode pad arranged between the first electrode pad and the second electrode pad, a wiring substrate on which the optical semiconductor chip is flip-chip mounted, including a fourth electrode pad, a fifth electrode pad, and a sixth electrode pad arranged between the fourth electrode pad and the fifth electrode pad, a first conductive material connecting the first electrode pad with the fourth electrode pad, a second conductive material connecting the second electrode pad with the fifth electrode pad, a third conductive material arranged between the first conductive material and the second conductive material, connecting the third electrode pad with the sixth electrode pad, and a resin provided in an area on the second conductive material side of the third conductive material between the optical semiconductor chip and the wiring substrate.

公开(公告)号：US20220317377A1

公开(公告)日：2022-10-06

申请号：US17592801

申请日：2022-02-04

Applicant: FUJITSU OPTICAL COMPONENTS LIMITED

Inventor： Kenta KANNARI ,  Toshio ISHII

IPC: G02B6/293 ,  G02F1/21 ,  G02B6/12

Abstract: An optical transmission apparatus includes an emitter that emits an optical signal in accordance with a bias current, and a Mach-Zehnder optical modulator that optically modulates the optical signal in accordance with an electrical signal. The optical modulator includes a detector that detects a temperature inside the optical modulator, and a controller that, when detecting activation of a power supply, controls the temperature inside the optical modulator such that the temperature detected by the detector reaches a target temperature.

公开(公告)号：US20220303018A1

公开(公告)日：2022-09-22

申请号：US17685043

申请日：2022-03-02

Applicant: FUJITSU OPTICAL COMPONENTS LIMITED

Inventor： Tomohisa ISHIKAWA

IPC: H04B10/54 ,  H04B10/80 ,  H04B10/293

Abstract: A control device of modulating signal generates high-side signal and low-side signal. The high-side signal takes level in accordance with level of AC component of a monitor signal obtained by photoelectric conversion of modulated light, when the polarity of the AC component is positive, or its magnitude is zero. The high-side signal further takes constant level when the polarity of the AC component is negative. The low-side signal takes constant level when the polarity of the AC component is positive. The low-side signal further takes level in accordance with level of the AC component when the polarity of the AC component is negative, or its magnitude is zero. Then, the control device adjusts level of the modulating signal based on a greatest value of absolute values of levels taken by the high-side signal and a greatest value of absolute values of levels taken by the low-side signal.

公开(公告)号：US20220294534A1

公开(公告)日：2022-09-15

申请号：US17580234

申请日：2022-01-20

Applicant: Fujitsu Optical Components Limited

Inventor： Takeyasu Tomioka ,  Shuichi Yasuda

IPC: H04B10/54 ,  H04B10/69

Abstract: An optical transmitter includes an optical modulator, a tunable optical filter, a temperature sensor, and a processor. The tunable optical filter is provided on an output side of the optical modulator and transmits light of a frequency corresponding to a control voltage. The temperature sensor detects a temperature around the tunable optical filter. The processor detects an optical loss occurring in the tunable optical filter, calculates a width of a range of the control voltage in which the detected optical loss is smaller than a specified threshold, adjusts the control voltage based on the temperature detected by the temperature sensor, and shifts the control voltage by a specified amount that is larger than zero and smaller than or equal to a half of the calculated width of the range when the optical loss is larger than or equal to the threshold.

公开(公告)号：US11418180B2

公开(公告)日：2022-08-16

申请号：US17166844

申请日：2021-02-03

Applicant: Fujitsu Optical Components Limited

Inventor： Toshio Ishii

IPC: H03K5/14 ,  H04L27/36 ,  H04L25/03 ,  H03G5/16

Abstract: An equalizer has a first tapped delay line in which N taps (N is a positive integer) are connected in cascade, a second tapped delay line having one tap and connected in parallel with the first tapped delay line, a first multiplier configured to multiply signals extracted from the N taps by corresponding coefficients, a second multiplier configured to multiply a signal output from the second tapped delay line by a second coefficient, and an adder configured to add products of the first multiplier and a product of the second multiplier. The first tapped delay line has a fixed delay, and the second tapped delay line has a variable delay changeable at a 1/M resolution of the fixed delay, where M is a number greater than 1.

公开(公告)号：US11309971B2

公开(公告)日：2022-04-19

申请号：US17135593

申请日：2020-12-28

Applicant: Fujitsu Optical Components Limited

Inventor： Tetsuji Yamabana ,  Tsuyoshi Morishita

IPC: H04B10/50 ,  H04B10/556 ,  H04B10/564

Abstract: Controller and control method are provided. In particular, a controller is disclosed as being configured to hold intensities of a monitor signal, which changes according to an output from a region in a device, before and after altering a state of a portion in the region and control the state of the portion based on a difference between the held intensities.

公开(公告)号：US20220082876A1

公开(公告)日：2022-03-17

申请号：US17391185

申请日：2021-08-02

Applicant: Fujitsu Optical Components Limited

Inventor： Masaki Sugiyama

IPC: G02F1/035

Abstract: An optical device includes an optical modulator formed on a substrate. The optical device includes: a signal electrode for the optical modulator that is formed on the substrate; a ground electrode for the optical modulator that is formed on the substrate; an optical waveguide that is provided in a region between the signal electrode and the ground electrode; a first buffer region that is formed between the optical waveguide and the substrate; and second buffer regions that are formed between the optical waveguide and the signal electrode and between the optical waveguide and the ground electrode. A permittivity of the second buffer regions is higher than a permittivity of the first buffer region.

公开(公告)号：US20210325761A1

公开(公告)日：2021-10-21

申请号：US17169983

申请日：2021-02-08

Applicant: Fujitsu Optical Components Limited

Inventor： Shuntaro MAKINO ,  Yoshinobu KUBOTA ,  Yasuhiro OHMORI ,  Masaharu DOI ,  Shintaro TAKEUCHI

IPC: G02F1/225 ,  F21V8/00 ,  G02F1/03

Abstract: An optical waveguide device has a substrate, an intermediate layer, a thin-film LN layer containing an X-cut lithium niobate, and a buffer layer stacked on the substrate, and an optical waveguide having a ridge shape formed in the thin-film LN layer. The optical waveguide device includes a plurality of electrodes provided, respectively, at a first side and a second side of the optical waveguide. The electrodes are disposed so that respective bottom surfaces thereof are at positions lower than a position of a surface of the buffer layer.

公开(公告)号：US11143889B2

公开(公告)日：2021-10-12

申请号：US16848108

申请日：2020-04-14

Applicant: FUJITSU OPTICAL COMPONENTS LIMITED

Inventor： Masaki Sugiyama

IPC: G02F1/035 ,  G02F1/025 ,  G01R19/165 ,  G01M11/00 ,  G01R31/00 ,  G01R1/067 ,  H04B10/66 ,  H04B10/50 ,  G02F1/015

Abstract: An optical transmission device includes: a substrate; a waveguide that is provided in the substrate and transmits an optical signal; a signal wiring that is provided in the substrate and transmits an electric signal; and a silicon wiring that is provided in the substrate and is silicon added with an impurity. The signal wiring is placed in an area of the substrate, the area being away from an end of the substrate by a predetermined distance or more. One end of the silicon substrate is connected to the signal wiring, and the other end of the silicon wiring extends to the end of the substrate.