Electrooptical modulator temperature control structure applied to residual amplitude modulation suppression

Abstract

The invention discloses an electro-optical modulator temperature control structure applied to residual amplitude modulation suppression, relates to the field of electro-optical modulator temperature control, and aims to solve the problem of non-uniform temperature of an electro-optical modulator. The device comprises an outer-layer heat shielding structure, an inner-layer heat shielding structure, an electro-optical modulator and a semiconductor chilling plate, the electro-optical modulator is arranged in the inner-layer heat shielding structure, and the inner-layer heat shielding structure is arranged in the outer-layer heat shielding structure. The semiconductor chilling plate is arranged between the outer-layer heat shielding structure and the inner-layer heat shielding structure and used for controlling the temperature of the inner shielding structure. The double-layer heat shielding structure combining the outer layer heat shielding structure and the inner layer heat shielding structure effectively solves the problem of non-uniform temperature of the electro-optical modulator in the prior art.

Description

Technical Field

[0001] The invention relates to the field of temperature control of electro-optic modulators, and in particular to a temperature control structure of an electro-optic modulator used for suppressing residual amplitude modulation. Background Art

[0002] Ultrastable narrow-linewidth lasers have extremely high frequency stability and extremely narrow linewidth, and have important applications in time-frequency transfer, optical frequency standards, ultrastable microwave signal generation, precision laser spectroscopy, gravitational wave detection, and basic physics experiments. Usually, ultrastable narrow-linewidth laser systems use the PDH method to lock the laser frequency to the resonant frequency of the optical reference cavity to achieve laser frequency stability.

[0003] However, due to the non-ideal effects of the electro-optic modulator, there is also residual amplitude modulation in the phase modulation process required to generate the error signal. The generated error signal will be superimposed on a time-varying DC bias, causing the locked laser frequency to deviate from the resonant frequency of the optical reference cavity, thereby deteriorating the frequency stability of the ultra-stable narrow-linewidth laser.

[0004] Temperature change is one of the main factors that cause residual amplitude modulation. Precise temperature control of the electro-optic modulator is an effective means to suppress residual amplitude modulation.

[0005] At present, the temperature control of the electro-optic modulator is usually achieved by directly contacting a semiconductor cooler and a temperature sensor on its outer surface. Since the electro-optic modulator is directly in contact with the ambient atmosphere in this solution, the semiconductor cooler as a temperature control actuator cannot cover all the outer surfaces of the electro-optic modulator, and the thermal uniformity and temperature control accuracy of the electro-optic modulator cannot be guaranteed. Summary of the invention

[0006] The present specification provides an electro-optic modulator temperature control structure applied to residual amplitude modulation suppression, so as to solve the problem of uneven temperature of the electro-optic modulator.

[0007] It includes an outer heat shielding structure, an inner heat shielding structure, an electro-optic modulator and a semiconductor cooling sheet;

[0008] The electro-optic modulator is arranged in the inner heat shielding structure, the inner heat shielding structure is arranged in the outer heat shielding structure, and the semiconductor cooling plate is arranged between the outer heat shielding structure and the inner heat shielding structure and is used to control the temperature of the inner heat shielding structure.

[0009] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided by some embodiments of the present application, a thermistor is attached to the inner heat shielding structure.

[0010] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided by some embodiments of the present application, an insulating material is provided between the outer heat shielding structure and the inner heat shielding structure.

[0011] According to some embodiments of the present application, a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression is provided, wherein both the outer heat shielding structure and the inner heat shielding structure are provided with threaded holes, and the outer heat shielding structure and the inner heat shielding structure are fixedly connected by screws adapted to the threaded holes.

[0012] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided in some embodiments of the present application, the screws for fixing the outer heat shielding structure and the inner heat shielding structure are made of insulating material.

[0013] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided by some embodiments of the present application, line openings are provided on both sides of the outer heat shielding structure and the inner heat shielding structure.

[0014] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided by some embodiments of the present application, the outer heat shielding structure is provided with at least one SMA radio frequency signal interface and one micro 9-pin serial port.

[0015] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided by some embodiments of the present application, the outer heat shielding structure is made of aluminum.

[0016] According to a temperature control structure of an electro-optic modulator for residual amplitude modulation suppression provided in some embodiments of the present application, the inner heat shielding structure is made of brass.

[0017] At least one of the above technical solutions adopted in the embodiments of this specification can achieve the following beneficial effects:

[0018] A double-layer heat shielding structure combining an outer heat shielding structure and an inner heat shielding structure is adopted, and an electro-optic modulator is wrapped inside the heat shielding structure. A semiconductor refrigerator as a temperature actuator controls the temperature of the inner heat shielding layer, so that the inner heat shielding structure layer has a uniform temperature. A thermistor as a temperature sensor detects the temperature of the inner heat shielding layer. The outer heat shielding structure layer conducts internal heat to ensure that the temperature of the inner heat shielding layer is stable, providing a uniform, stable and quickly responsive temperature environment for the electro-optic modulator. The temperature of the inner shielding structure is controlled by setting a direct contact semiconductor cooling sheet, thereby solving the problem of uneven temperature of the electro-optic modulator in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0020] Figure 1 This is a schematic diagram of the temperature control structure of an electro-optic modulator provided in one embodiment of this specification.

[0021] In the figure: 1. Outer heat shielding structure; 2. Inner heat shielding structure; 3. Electro-optic modulator; 4. SMA RF signal interface; 5. Micro 9-pin serial port. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0023] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of the temperature control structure of the electro-optic modulator provided in an embodiment of this specification, referring to Figure 1 , the present embodiment provides an electro-optic modulator temperature control structure for residual amplitude modulation suppression, comprising an outer heat shielding structure 1, an inner heat shielding structure 2, an electro-optic modulator 3 and a semiconductor cooling sheet;

[0025] The electro-optic modulator 3 is arranged in the inner heat shielding structure 2, the inner heat shielding structure 2 is arranged in the outer heat shielding structure 1, and the semiconductor cooling plate is arranged between the outer heat shielding structure 1 and the inner heat shielding structure 2 and is used to control the temperature of the inner heat shielding structure 2.

[0026] In specific implementation, the outer heat shielding structure 1 and the inner heat shielding structure 2 are rectangular box-type structures, the outer heat shielding structure 1 wraps the inner heat shielding structure 2, and a double-layer heat shielding structure combining the outer heat shielding structure 1 and the inner heat shielding structure 2 is adopted. The electro-optical modulator 3 is placed in the inner heat shielding structure 2, and the semiconductor refrigerator used as a temperature actuator controls the temperature of the inner heat shielding structure 2 so that the inner heat shielding structure 2 has a uniform temperature. By setting a semiconductor cooling plate that makes the outer heat shielding structure 1 directly contact the inner heat shielding structure 2, the temperature of the inner heat shielding structure 2 is controlled, thereby solving the problem of uneven temperature of the electro-optical modulator in the prior art. The structure has higher temperature control accuracy, can directly control the electro-optical modulator 3 at a constant temperature, and can also perform feedback control on the temperature. Both methods can achieve residual amplitude modulation suppression of the electro-optical modulator 3.

[0027] In some embodiments, a thermistor is attached to the inner heat shielding structure 2 .

[0028] In specific implementation, the thermistor as a temperature sensor detects the temperature of the inner heat shielding structure 2, and the outer heat shielding structure 1 conducts internal heat to ensure the temperature of the inner heat shielding structure 2 is stable, providing a uniform, stable and fast-responding temperature environment for the electro-optic modulator 3.

[0029] In some embodiments, a heat insulating material is provided between the outer heat shielding structure 1 and the inner heat shielding structure 2 for isolation.

[0030] During specific implementation, thermal insulation material is provided to prevent thermal contact between the two layers of heat shielding structures.

[0031] In some embodiments, threaded holes are provided on the outer heat shielding structure 1 and the inner heat shielding structure 2, and the outer heat shielding structure 1 and the inner heat shielding structure 2 are fixedly connected by screws adapted to the threaded holes. As a preferred embodiment, the screws used to fix the outer heat shielding structure 1 and the inner heat shielding structure 2 are made of insulating material.

[0032] In specific implementation, the inner heat shielding structure 2 and the outer heat shielding structure 1 are fixed through threaded holes at four corners and screws adapted to the threaded holes. The screws used for fixing are also made of insulating material, which can further avoid thermal contact between the two layers of heat shielding structures.

[0033] In some embodiments, circuit openings are provided on both sides of the outer heat shielding structure 1 and the inner heat shielding structure 2 .

[0034] In specific implementation, both sides of the outer heat shielding structure 1 and the inner heat shielding structure 2 are not completely sealed, and line openings are left for the optical fiber and electrical signal line connected to the internal electro-optical modulator 3 to pass through.

[0035] In some embodiments, the outer heat shielding structure 1 is provided with at least one SMA radio frequency signal interface 4 and one micro 9-pin serial port 5 .

[0036] During specific implementation, the SMA RF signal interface is used to apply RF modulation signal to the electro-optical modulator; the micro 9-pin serial port line interface is used to monitor the actual temperature of the inner thermal shielding structure and control the heating or cooling of the semiconductor refrigerator. The SMA RF signal interface and the micro 9-pin serial port line interface are both mature interface structures in the prior art and will not be repeated here.

[0037] In some embodiments, the outer heat shielding structure 1 is made of aluminum, and the inner heat shielding structure 2 is made of brass.

[0038] During specific implementation, the inner heat shielding structure 2 is made of brass material with higher heat capacity, so that the temperature of the inner heat shielding structure 2 is more uniform.

[0039] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A temperature control structure for an electro-optic modulator for residual amplitude modulation suppression, characterized in that: It comprises an outer heat shielding structure (1), an inner heat shielding structure (2), an electro-optic modulator (3) and a semiconductor cooling sheet; The electro-optic modulator (3) is arranged in the inner heat shielding structure (2), the inner heat shielding structure (2) is arranged in the outer heat shielding structure (1), and the semiconductor cooling plate is arranged between the outer heat shielding structure (1) and the inner heat shielding structure (2) and is used to control the temperature of the inner heat shielding structure (2).

2. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 1, characterized in that: A thermistor is attached to the inner heat shielding structure (2).

3. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 2, characterized in that: A heat insulating material is provided between the outer heat shielding structure (1) and the inner heat shielding structure (2).

4. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 1, characterized in that: The outer heat shielding structure (1) and the inner heat shielding structure (2) are both provided with threaded holes, and the outer heat shielding structure (1) and the inner heat shielding structure (2) are fixedly connected by screws adapted to the threaded holes.

5. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 4, characterized in that: The screws used to fix the outer heat shielding structure (1) and the inner heat shielding structure (2) are made of heat insulating material.

6. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 1, characterized in that: Line openings are provided on both sides of the outer heat shielding structure (1) and the inner heat shielding structure (2).

7. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 1, characterized in that: The outer heat shielding structure (1) is provided with at least one SMA radio frequency signal interface (4) and one micro 9-pin serial port (5).

8. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 1, characterized in that: The outer heat shielding structure (1) is made of aluminum.

9. The electro-optic modulator temperature control structure for residual amplitude modulation suppression according to claim 1, characterized in that: The inner heat shielding structure (2) is made of brass.

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