US 12,111,559 B2
Optical switch
Yusuke Muranaka, Musashino (JP); Tatsushi Nakahara, Musashino (JP); and Toshikazu Hashimoto, Musashino (JP)
Assigned to Nippon Telegraph and Telephone Corporation, Tokyo (JP)
Appl. No. 17/768,774
Filed by Nippon Telegraph and Telephone Corporation, Tokyo (JP)
PCT Filed Oct. 16, 2019, PCT No. PCT/JP2019/040707
§ 371(c)(1), (2) Date Apr. 13, 2022,
PCT Pub. No. WO2021/075002, PCT Pub. Date Apr. 22, 2021.
Prior Publication US 2023/0095427 A1, Mar. 30, 2023
Int. Cl. G02F 1/313 (2006.01); G02B 6/12 (2006.01); G02F 1/015 (2006.01)
CPC G02F 1/3136 (2013.01) [G02B 6/12 (2013.01); G02F 1/015 (2013.01); G02F 1/313 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An optical switch having one optical input port, and N-th optical output ports where N is an integer of 2 or more,
the optical switch, comprising:
2-input 2-output optical switches connected in a multistage for branching an optical signal inputted to the optical input port into N-th optical signals;
N-th optical gates respectively provided at the optical output ports;
driving circuits for operating the 2-input 2-output optical switches; and
driving circuits for operating the N-th optical gates independently of the 2-input 2-output optical switches;
wherein the driving circuits for operating the 2-input 2-output optical switches are integrated adjacent to a control electrode set on waveguides included in the 2-input 2-output optical switches,
the driving circuits for operating the N-th optical gates are integrated adjacent to a control electrode set on waveguides included in the N-th optical gates,
the waveguide included in the 2-input 2-output optical switch and the waveguide included in the N-th optical gates each have a p layer, an i layer, and an n layer sequentially formed on a semi-insulating substrate,
a trench reaching the semi-insulating substrate is included between the 2-input 2-output optical switches and the N-th optical gates, and the trench isolates the p layer in an area of the 2-input 2-output optical switches and a p layer in an area of the N-th optical gates.