Abstract:
The invention relates to an electro-optic Mach-Zehnder modulator arrangement, comprising - a first optical waveguide (11) forming a first arm of the Mach-Zehnder modulator (1, 100); - a second optical waveguide (12) forming a second arm of the Mach-Zehnder modulator (1, 100); - an electrode arrangement (2) comprising at least one first waveguide electrode (21, 210) output port (441, 4410) coupled to the first waveguide electrodes (21, 210)and at least one second waveguide electrode (22, 220) arranged on top of a capacitive segment (111, 1110, 121, 1210) of the first and the second optical waveguide (11, 12), respectively, such that a voltage can be applied across the capacitive segments (111, 1110, 121, 1210) of the first and second optical waveguide (11, 12); - at least one driver unit (41, 410) for supplying a voltage (V) to the electrode arrangement (2), the driver unit (41, 410) comprising at least a first output port (441, 4410) coupled to the first waveguide electrodes (21, 210) and a second output port (442, 4420) coupled to the second waveguide electrodes (22, 220), wherein - the driver unit (41) is configured to supply a first varying signal (S+) to the first waveguide electrodes (21) via the first output port (441) and to supply a second varying signal (S-) to the second waveguide electrodes (22) via the second output port (442); and - a non-grounded conductive region (3, 30) via which the capacitive segment (111, 1110) of the first optical waveguide (11) is connected to the capacitive segment (121, 1210) of the second optical waveguide (12) such that the first and second waveguide electrodes (21, 210, 22, 220) are capacitively coupled to one another. The invention also relates to a method for operating a Mach-Zehnder modulator arrangement.
Abstract:
An electrical waveguide transmission device (15) accepts a differential electrical input signal (e.g., S+ and S-) propagating along two separate signal conductors (1,2) with grounded electrical return paths, and outputs the differential input signal to a series push-pull traveling wave electrode Mach-Zehnder optical modulator (10) over a pair of output conductors (8A.8B) that act as a return path for each other and provide a desired characteristic impedance matching that of the Mach-Zehnder optical modulator.
Abstract:
This writing discloses high-speed, single-drive and dual-drive external optical modulation devices that reduce the voltage and power required to amplify and modulate electrical signals onto an optical carrier. Two primary components of an optical transmitter (200), namely, the modulator (202) and driver (204), are integrated, and preferably hybridly integrated, in a single package, thereby eliminating many of the cable connector interfaces that add loss, complexity and cost to the system. Further, integration frees the devices from the standardized impedance (i.e. 50 ohm) constraints that reduce performance, thereby enabling the design of optimized, low voltage, hybridly integrated modulation devices.
Abstract:
The optical system comprises two optical paths (P1, P2), and an arrangement for changing the length of the two paths including two phase modulators (M1. M2) one coupled to each of the paths. A driving system (Figure 3) applies power to the phase modulators to drive them in the same direction and to change the amount of power applied to the phase modulators in opposite directions so as to change the length of each optical path in a different direction. As a result, the relationship between the changes in the amount of power applied to the modulators and the resulting changes in the phase of light beams passing through the device becomes substantially linear.
Abstract:
A silicon-based optical modulator structure includes one or more separate localized heating elements for changing the refractive index of an associated portion of the structure and thereby providing corrective adjustments to address unwanted variations in device performance. Heating is provided by thermo-optic devices such as, for example, silicon-based resistors, suicide resistors, forward-biased PN junctions, and the like, where any of these structures may easily be incorporated with a silicon-based optical modulator. The application of a DC voltage to any of these structures will generate heat, which then transfers into the waveguiding area. The increase in local temperature of the waveguiding area will, in turn, increase the refractive index of the waveguiding in the area. Control of the applied DC voltage results in controlling the refractive index.
Abstract:
본 발명은 인접 비트 사이의 위상 차이를 정보로 하여 전송하는 광학적 디피에스케이(DPSK) 변조 장치 및 방법에 관한 것이다. 본 발명에 따른 전기적으로 대역 제한된 광학적 DPSK 변조 장치는, 광원과; NRZ 신호를 생성하는 NRZ 신호 생성기와; 상기 NRZ 신호 생성기에 의하여 생성된 NRZ 신호를 차동 신호로 코딩하는 프리코더와; 상기 프리코더에 의하여 코딩된 신호를 전송 속도의 80% ~ 60%의 범위에서 전기적으로 대역폭 제한하는 전기적 저대역 통과 필터; 및 상기 전기적 저대역 통과 필터에 의하여 대역폭이 제한된 전기 신호를 가지고, 상기 광원으로부터 입력되는 빛을 DPSK 신호로 변조하는 위상 변조기를 포함하는 것을 특징으로 한다. DPSK, Band-limited, transmitter, modulation format
Abstract:
실리콘-기반 광학 변조기 구조(20)는 상기 구조의 연관된 부분의 굴절율을 변화시키고 그에 따라 장치 성능의 원치 않는 변동들을 처리하기 위해 교정하는 조정들을 제공하기 위한 하나 또는 그 이상의 분리된 지역적인 가열 엘리먼트들(22/24)을 포함한다. 가열은 예를 들어 실리콘-기반 레지스터들, 규소화합물 레지스터들, 정방향-바이어스된 PN 접합들, 및 그와 유사한 것과 같은 열-광학 장치들에 의해 제공되며, 이러한 구조들 중 어떤 것은 실리콘-기반 광학 변조기와 용이하게 결합될 수 있다. 이러한 구조들 중 어떤 것으로의 DC 전압의 인가는 열을 생성할 것이며, 상기 열은 도파관 영역 내부로 전달된다. 도파관 영역의 지역적인 온도 증가는, 차례로, 상기 영역에 있는 도파관의 굴절율을 증가시킬 것이다. 상기 인가된 DC 전압에 대한 제어는 상기 굴절율을 제어하는 결과를 낳는다.
Abstract:
본 발명은 인접 비트 사이의 위상 차이를 정보로 하여 전송하는 광학적 디피에스케이(DPSK) 변조 장치 및 방법에 관한 것이다. 본 발명에 따른 전기적으로 대역 제한된 광학적 DPSK 변조 장치는, 광원과; NRZ 신호를 생성하는 NRZ 신호 생성기와; 상기 NRZ 신호 생성기에 의하여 생성된 NRZ 신호를 차동 신호로 코딩하는 프리코더와; 상기 프리코더에 의하여 코딩된 신호를 전기적으로 대역폭 제한하는 전기적 저대역 통과 필터; 및 상기 전기적 저대역 통과 필터에 의하여 대역폭이 제한된 전기 신호를 가지고, 상기 광원으로부터 입력되는 빛을 DPSK 신호로 변조하는 위상 변조기를 포함하는 것을 특징으로 한다.
Abstract:
A differential TWE MZM includes a differential driver, first and second capacitors, and first and second terminations. The differential driver includes a first differential output and a second differential output that collectively form a differential pair. The first differential output is DC coupled to a cathode of a first arm optical phase shifter of a TWE MZM. The second differential output is DC coupled to a cathode of a second arm optical phase shifter of the TWE MZM. The first capacitor AC couples the second differential output to an anode of the first arm optical phase shifter. The second capacitor AC couples the first differential output to an anode of the second arm optical phase shifter. The first and second terminations are coupled to the cathode and the anode of, respectively, the first or second arm optical phase shifter.