CN-224232008-U - Optical module capable of controlling constant wavelength of laser

CN224232008UCN 224232008 UCN224232008 UCN 224232008UCN-224232008-U

Abstract

The utility model relates to the technical field of optical modules, in particular to an optical module capable of controlling the wavelength of a laser to be constant. Comprising the following steps: the laser is arranged in the BOX or the TO, and is characterized by further comprising a second thermistor which is arranged in the BOX or the TO and in an area beyond the TEC and is used for monitoring the temperature of gas in the cavity. According TO the scheme, the temperature of the laser can be controlled more accurately by placing an extra thermistor in the BOX or TO and in the area outside the TEC, so that the constant control of the wavelength is realized. In the practical test, the fluctuation is within the range of +/-0.01 nm, so that the yield and performance of the optical module are improved, and the transmission stability of the DWDM optical module system is optimized.

Inventors

LI TIANRUI
SONG YUNPENG
HE WEISHENG
HUANG YU

Assignees

光为科技(广州)有限公司

Dates

Publication Date: 20260512
Application Date: 20250427

Claims (6)

1. The optical module capable of controlling the laser TO be constant in wavelength is characterized by comprising a laser, a ceramic substrate, a TEC and at least two first thermistors, wherein the first thermistors and the laser are fixed on the ceramic substrate through silver colloid, the ceramic substrate is fixed on a cold surface of the TEC, the laser is arranged in a BOX or a TO, the second thermistors are arranged in the BOX or the TO and are arranged in areas outside the TEC, and the second thermistors are used for monitoring the temperature of gas in a cavity.
2. A controllable laser wavelength constant optical module according to claim 1, wherein the laser is a DWDM laser with a wavelength in the range 1470nm to 1625nm.
3. The controllable laser wavelength constant optical module according to claim 1 or 2, further comprising an MCU for measuring a resistance signal of the thermistor, calculating a target temperature of the TEC according to a preset linear relationship, and adjusting the TEC to make the laser temperature reach the target temperature.
4. A controllable laser wavelength constant optical module as claimed in claim 3, wherein the linear relationship is T 1 =k T 2 +b, wherein T 1 is the target temperature of the TEC, T 2 is the temperature of the gas in the cavity monitored by the second thermistor, and k and b are constants obtained through statistics of a plurality of module tests.
5. The optical module according to claim 4, wherein the value ranges of k and b are dynamically corrected by normal temperature, high temperature and low temperature three-point calibration, and the values of k and b are calculated and written into the MCU.
6. The optical module of claim 5, wherein the MCU reads the resistance of the second thermistor in real time during operation, calculates the temperature value of T2, calculates the target value of T1 according to a linear relationship, and adjusts the TEC to make T1 reach the target value, thereby accurately controlling the laser wavelength.

Description

Optical module capable of controlling constant wavelength of laser Technical Field The utility model relates to the technical field of optical modules, in particular to an optical module capable of controlling the wavelength of a laser to be constant. Background In the design of an optical module, a laser is an important component, and the wavelength of the laser varies with temperature according to the characteristics of the laser. For DWDM optical modules, tight wavelength control is required. DWDM refers to dense wavelength division multiplexing (DENSE WAVELENGTH Division Multiplexing) technology. This is an efficient way of transmitting data in an optical fiber by multiplexing a plurality of optical signals of different wavelengths into one optical fiber. DWDM technology takes advantage of the wavelength characteristics of light, allowing multiple independent optical signals to be transmitted simultaneously on a single optical fiber, each occupying a different wavelength channel. This has the advantage that the transmission capacity of the optical fiber can be significantly increased without the need to add more physical optical fibers. DWDM typically has a wavelength spacing of only 0.4nm, 0.8nm. At present, the effect of controlling the wavelength is achieved mainly by controlling the temperature of a laser through a TEC in the market. In practical use, since the wavelength cannot be directly measured, temperature is generally used as feedback to adjust the TEC, and temperature is generally collected and fed back by using an NTC thermistor. In practical applications, the thermistor and the laser are on the same substrate, but the upper surface of the laser is exposed to air, so that the actual temperature of the laser and the temperature of the substrate deviate to a certain extent. Therefore, when the TEC is kept at a constant temperature, the laser is not in a constant temperature state, and the wavelength still has certain fluctuation. May be out of the range of 0.4 nm. In addition, the wavelength range used by DWDM is 1470 nm-1625 nm, so that the chirp phenomenon is easy to generate, the influence of the chirp can be reduced by controlling the constant wavelength, and the stability of long-distance transmission is improved. Accordingly, in view of the above-mentioned problems, there is a need for an optical module capable of reducing the chirp phenomenon and improving the long-distance transmission stability. Disclosure of utility model For the current controllable laser, the wavelength still has certain fluctuation under the constant temperature state. Possibly exceeding the range of 0.4nm, and being easy to generate chirp phenomenon, the application provides an optical module capable of controlling the laser wavelength to be constant so as to solve the problems. In order to achieve the above purpose, the present utility model is realized by the following technical scheme: The embodiment of the application discloses an optical module capable of controlling the constant wavelength of a laser, which comprises the laser, a ceramic substrate, a TEC (thermoelectric cooler) and at least two first thermistors, wherein the first thermistors and the laser are fixed on the ceramic substrate through silver colloid, the ceramic substrate is fixed on the cold surface of the TEC, and the laser is arranged in a BOX or TO, and is characterized by further comprising the following components: and the second thermistor is arranged in the BOX or the TO and is used for monitoring the temperature of the gas in the cavity, and the area is outside the TEC. Optionally, the laser is a DWDM laser, and the wavelength range is 1470nm to 1625nm. Optionally, the temperature sensor further comprises an MCU, wherein the MCU is used for measuring a resistance signal of the thermistor, calculating a target temperature of the TEC according to a preset linear relation, and adjusting the TEC to enable the temperature of the laser to reach the target temperature. Optionally, the linear relationship is T 1 =kT 2 +b, wherein T 1 is the target temperature of the TEC, T 2 is the temperature of the gas in the cavity monitored by the second thermistor, and k and b are constants obtained through statistics of a plurality of module tests. Optionally, the value ranges of k and b are dynamically calibrated through normal temperature, high temperature and low temperature three points Optionally, the MCU reads the resistance value of the second thermistor in real time during operation, calculates the temperature value of T2, calculates the target value of T1 according to the linear relationship, and adjusts the TEC to make T1 reach the target value, thereby accurately controlling the laser wavelength. The technical effects are as follows: By adopting the technical scheme of the utility model, the temperature of the laser can be controlled more accurately by placing an extra thermistor in the region outside the TEC in the BOX or the TO, so that th