Novel high-power stability ASE light source structure
By designing a dual-path forward optical path and a Gaussian filter, combined with a temperature control circuit and a light source driver, the wavelength instability problem of the ASE light source across the entire temperature range was solved, achieving high stability and high power output for the fiber optic gyroscope and improving its scaling factor performance.
Patent Information
- Application Number
- CN202422950404.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-02
- Publication Date
- 2025-11-07
- Estimated Expiration
- 2034-12-02
AI Technical Summary
The average wavelength stability of existing ASE light sources is difficult to achieve the accuracy requirement of 30ppm across the entire temperature range, which affects the scaling factor performance of fiber optic gyroscopes. In particular, temperature changes across the entire temperature range cause instability in the light source wavelength.
Employing a dual-path forward optical path, wavelength division multiplexer, Gaussian filter, and light source driving and temperature control circuitry, the system optimizes the erbium-doped fiber length and pump power, combined with a Gaussian filter and a two-stage optical isolator, to achieve high stability and high power output of the light source. Precise temperature control is achieved using the integrated control chip MAX1978.
It achieves an average wavelength stability of better than 15ppm across the entire temperature range, significantly improving the scaling factor stability and output power of the fiber optic gyroscope, and meeting the requirements of high-precision fiber optic gyroscopes.
Smart Images
Figure CN223525804U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to optical fiber gyroscope technical field, especially relate to a novel high power stability ASE light source structure. BACKGROUND
[0002] Optical fiber gyroscope is the measuring instrument that utilizes Sagnac effect sensitive rotation angular velocity. It has high precision, low drift, high reliability and stability, strong anti-interference ability, fast response and other characteristics and advantages. Especially in high precision application field, optical fiber gyroscope will become important technology in the field of inertial measurement.
[0003] The spontaneous emission light source ASE used in ultra-high precision optical fiber gyroscope is an important key technology to realize high precision measurement. ASE light source has the characteristics of wide band, low coherence, high output power, good average wavelength stability, etc., and becomes the ideal light source selection of ultra-high precision optical fiber gyroscope. The average wavelength change of the light source is closely related to the scale factor of the optical fiber gyroscope, and the slight wavelength change will cause the scale factor to change by the same order of magnitude, so the average wavelength stability of the light source is very important to the scale factor stability, and the change of the scale factor directly affects the accurate measurement of the angular velocity of the optical fiber gyroscope, and further affects the detection precision. Especially in ultra-high precision optical fiber gyroscope, the average wavelength stability becomes the most important design index of the light source.
[0004] In the ultra-high precision optical fiber gyroscope navigation system, the scale factor stability is required to be extremely strict, especially in the full temperature range (-45℃~+70℃), it is required to reach 30ppm or even higher precision. However, the average wavelength stability of the current ASE light source can usually only reach about 100ppm in the full temperature range, although it can be improved to a certain extent through compensation, but it is still difficult to meet such high precision scale factor requirement. This limitation has become an important bottleneck restricting the further improvement of the scale factor performance of the optical fiber gyroscope.
[0005] The change of the average wavelength of the light source is mainly affected by the external environmental temperature. In the ASE light source, the main factors causing the average wavelength change are as follows:
[0006] The first item is the center wavelength change caused by the temperature drift of the erbium-doped fiber spectrum in the absorption and radiation process, which reflects the intrinsic change rate of the erbium-doped fiber radiation wavelength to the temperature, and the size depends on the absorption cross section and emission cross section spectrum of the erbium-doped fiber.
[0007] The second item is the center wavelength shift caused by the temperature change of the pump wavelength. The laser diode in the pump laser is very sensitive to temperature, and the change of the external or internal temperature will cause the shift of the pump wavelength, thereby affecting the absorption efficiency of the pump. The population inversion along the erbium-doped fiber is a function of the pump absorption efficiency, and with the change of the pump absorption efficiency, the average wavelength of the spectrum will also change accordingly.
[0008] The third item is the fluctuation of the pump power caused by the temperature change, which causes the deformation of the ASE light source output spectrum, thereby affecting the average wavelength of the spectrum.
[0009] In summary, to improve the stability of the average wavelength of the ASE light source, it is necessary to complete the reasonable design of the optical path structure and parameters, the design of the parameters of isolation and filtering, and the stable pump working temperature and stable power and wavelength output. Utility model content
[0010] The utility model discloses a novel high-power stability ASE light source structure, can realize the average wavelength stability and high-power output of light source in full temperature range, thereby promote the scale factor performance of fiber gyroscope, to solve the problem of the background art in the foregoing.
[0011] To realize the above-mentioned purpose, the utility model provides the following technical scheme: a novel high-power stability ASE light source structure, including double -pass forward optical path, gauss type filter and light source drive and temperature control circuit, the gauss type filter and double -pass forward optical path are connected, and the double -pass forward optical path and light source drive and temperature control circuit are connected.
[0012] The double -pass forward optical path is composed of pump laser, wave division multiplexer, high -density erbium -doped optical fiber, optical fiber reflector and filter isolator, the optical fiber reflector is connected with wave division multiplexer, and the wave division multiplexer is connected with high -density erbium -doped optical fiber, and the high -density erbium -doped optical fiber is connected with filter isolator, and the pump laser is connected with wave division multiplexer, and the light source drive and temperature control circuit are connected with pump laser, and the filter isolator is connected with gauss filter.
[0013] Further, the light source drive and temperature control circuit are divided into mutually independent temperature control circuit parts and light power control circuit parts.
[0014] Further, the wavelength of the wave division multiplexer is 980 / 1560nm.
[0015] Further, the gauss type filter filters the 1560nm peak of the natural spectrum output by the double -pass forward optical path.
[0016] Further, the filter isolator is a double -stage optical isolator.
[0017] Further, the light source driving and temperature control circuit comprises a TEC driving and a laser driving, and the TEC driving adopts an integrated control chip MAX1978.
[0018] The novel high-power stability ASE light source structure has the advantages that:
[0019] 1. The novel high-power stability ASE light source structure comprises a double-pass forward light path, and the double-pass forward light path comprises a pump laser, a wavelength division multiplexer, a high-concentration erbium-doped optical fiber, an optical fiber reflector and a filter isolator and the like. The light emitted by the pump laser is injected into the erbium-doped optical fiber through the wavelength division multiplexer, and spontaneous emission signals are generated in the forward and backward directions, respectively. The backward spontaneous emission signal (ASE light) is reflected by the optical fiber reflector and then passes through the erbium-doped optical fiber again to be amplified, and is superimposed with the forward spontaneous emission signal to generate stronger forward output power, thereby realizing higher pump efficiency than the single-pass structure. The high-performance driving circuit comprises a TEC driving and a laser driving. Through optimization of the erbium-doped optical fiber length and the pump power, the novel high-power stability ASE light source structure realizes full-temperature average wavelength stability of more than 15ppm.
[0020] 2. The novel high-power stability ASE light source structure adopts a double-stage optical isolator, which can effectively prevent the 1550nm output light from returning to the erbium-doped optical fiber to cause lasing.
[0021] 3. The wavelength division multiplexer in the novel high-power stability ASE light source structure works at 980 / 1550nm wavelength, is used for coupling the 980nm pump light into the erbium-doped optical fiber to excite 1550nm signal light, and couples the 1550nm light generated by the erbium-doped optical fiber to be output.
[0022] 4. The novel high-power stability ASE light source structure, the wavelength of the pump laser is 980nm, which provides stable pump light signals for the erbium-doped optical fiber.
[0023] 5. The Gaussian filter in the novel high-power stability ASE light source structure is used for filtering the 1560nm peak in the natural spectrum output by the double-pass forward light path, improving the stability of the scale factor, and suppressing the coherent noise in the fiber optic gyroscope.
[0024] 6. The novel high-power stability ASE light source structure adopts the TEC driving of the integrated control chip MAX1978, has the characteristics of small size and high temperature control precision, can realize temperature control precision of 0.001°C, and ensures that the temperature control precision is better than 0.3°C in the full-temperature range, thereby effectively maintaining the temperature control stability of the pump laser chip.
[0025] 7. The utility model discloses a scientific and reasonable design, through the test optimization of the length and pump power parameter of erbium-doped optical fiber, make the light source of double -pass forward structure realize the average wavelength stability of surpassing 15ppm in full temperature range, significantly improve the full temperature average wavelength stability of ASE light source, to improve the scale factor stability of ultrahigh precision optical fiber gyroscope.
[0026] Other features and advantages of the present utility model will be set forth in the following description of the application, and in part will become apparent to those skilled in the art from the description, or can be learned by practice of the present utility model. The objects and other advantages of the present utility model can be realized and obtained by the structure indicated in the description and drawings. BRIEF DESCRIPTION OF DRAWINGS
[0027] In order to more clearly illustrate the technical scheme in the embodiments of the present utility model or prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description, obviously, the drawings in the following description are some embodiments of the present utility model, and for those skilled in the art, on the premise of not creating laboriously, other drawings can also be obtained according to these drawings.
[0028] Figure 1 The ASE light source structure diagram according to the present utility model is shown;
[0029] Figure 2 The double -pass forward optical path structure diagram according to the present utility model is shown;
[0030] Figure 3 The natural spectrum spectrum shape diagram under different power of the ASE light source according to the present utility model is shown;
[0031] Figure 4 The output spectrum shape diagram after filtering according to the present utility model is shown;
[0032] Figure 5 The temperature control circuit diagram using MAX1978 according to the present utility model is shown;
[0033] Figure 6 The ASE light source full temperature power drift measurement result diagram according to the present utility model is shown;
[0034] Figure 7 The ASE light source full temperature average wavelength drift measurement result diagram according to the present utility model is shown. DETAILED DESCRIPTION
[0035] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely explained in combination with the drawings in the embodiments of the utility model, obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.
[0036] Please refer to Figures 1-7 The utility model provides a technical scheme:
[0037] A novel high-power stability ASE light source structure, comprising a double-pass forward light path, a Gaussian filter and a light source driving and temperature control circuit, wherein the Gaussian filter is connected with the double-pass forward light path, and the double-pass forward light path is connected with the light source driving and temperature control circuit.
[0038] The double-pass forward light path is composed of a pump laser, a wavelength division multiplexer, a high-concentration erbium-doped optical fiber, an optical fiber reflector and a filter isolator, wherein the optical fiber reflector is connected with the wavelength division multiplexer, the wavelength division multiplexer is connected with the high-concentration erbium-doped optical fiber, the high-concentration erbium-doped optical fiber is connected with the filter isolator, the pump laser is connected with the wavelength division multiplexer, the light source driving and temperature control circuit is connected with the pump laser, and the filter isolator is connected with the Gaussian filter.
[0039] The pump light is injected into the erbium-doped optical fiber through the wavelength division multiplexer, and amplified spontaneous emission signals (ASE) are generated in the forward and backward directions. The backward ASE light is reflected by the optical fiber reflector and then amplified again through the erbium-doped optical fiber, and superimposed with the forward ASE light to form higher forward output power. Therefore, the structure realizes higher pump efficiency than the single-pass structure. The output light is output after passing through the wavelength division multiplexer and the double-stage optical isolator.
[0040] The pump laser adopts a 980nm pump laser to provide pump light signals for the erbium-doped optical fiber,
[0041] The erbium-doped optical fiber is a high-concentration erbium ion optical fiber. When the erbium ions absorb the energy of pump photons, they are excited to high energy levels, then jump to intermediate energy levels and accumulate, thereby forming population inversion and generating amplified spontaneous emission signals.
[0042] The optical fiber reflector is used to avoid the return of 1550nm output light into the erbium-doped optical fiber to cause lasing phenomenon. Through experimental optimization of the length of the erbium-doped optical fiber and the pump power parameters, the light source with the double-pass forward structure realizes an average wavelength stability better than 15ppm in the full temperature range.
[0043] Further, the light source driving and temperature control circuit is divided into a temperature control circuit part and a light power control circuit part which are independent of each other.
[0044] Further, the wavelength of the wavelength division multiplexer is 980 / 1560nm.
[0045] The working wavelength of the wavelength division multiplexer is 980 / 1550nm, which is used for coupling 980nm pump light to an erbium-doped fiber to excite 1550nm signal light, and coupling 1550nm light generated by the erbium-doped fiber to be output.
[0046] Further, the Gaussian filter filters the 1560nm peak of the natural light spectrum output by the double-pass forward light path.
[0047] The Gaussian spectrum filter is used to filter the natural light spectrum output by the double-stage optical isolator into a Gaussian spectrum. The Gaussian spectrum has a gentle curve change, excellent central wavelength stability and good symmetry, which helps to suppress the coherent noise in the fiber optic gyroscope and reduce the nonlinear error of the scale factor. The filter spectrum is based on the gain peak characteristics of the natural light spectrum at 1560nm, and a suitable filter window is selected to retain the 1560nm peak and filter out other parts. The filter design takes into account the spectrum width and the spectrum symmetry in the full temperature range.
[0048] Further, the filter isolator is a double-stage optical isolator.
[0049] Further, the light source driving and temperature control circuit includes a TEC drive and a laser drive, and the TEC drive adopts an integrated control chip MAX1978.
[0050] The light source driving and temperature control circuit can realize accurate temperature control. The TEC drive adopts an integrated control chip MAX1978, has small size and high temperature control precision, and realizes 0.001°C temperature control stability through circuit optimization, and the temperature control precision of the pump laser chip in the full temperature range is better than 0.1°.
[0051] The light path and the circuit designed in the utility model are assembled into an ASE light source, and the light path parameters are determined through experiments. The light source is placed in a temperature box, and is tested under the temperature cycle condition of-45°C~+70°C, the average wavelength change is measured, and the result shows that the wavelength drift in the full temperature range is better than 15ppm, and the full temperature average wavelength stability is significantly improved. At the same time, the output power is detected by using a light power measuring device, and the result shows that the power change rate of the light source in the full temperature range is 0.83%
[0052] Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features therein can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.
Claims
1. A novel high power stable ASE light source structure, characterized by: The application relates to a natural light source, which comprises a double-pass forward light path, a Gaussian filter and a light source driving and temperature control circuit. The double-pass forward light path is composed of a pump laser, a wavelength division multiplexer, a high-concentration erbium-doped optical fiber, an optical fiber reflector and a filter isolator; the optical fiber reflector is connected with the wavelength division multiplexer; the wavelength division multiplexer is connected with the high-concentration erbium-doped optical fiber; the high-concentration erbium-doped optical fiber is connected with the filter isolator; the pump laser is connected with the wavelength division multiplexer; the light source driving and temperature control circuit is connected with the pump laser; and the filter isolator is connected with the Gaussian filter.
2. A novel high power stable ASE light source structure according to claim 1, characterized in that: The light source driving and temperature control circuit is divided into a temperature control circuit part and a light power control circuit part.
3. A novel high power stable ASE light source structure according to claim 2, characterized in that: The wavelength of the wavelength division multiplexer is 980 / 1560 nm.
4. The novel high power stable ASE light source structure according to claim 3, characterized in that: The Gaussian filter filters the 1560 nm peak of the natural light spectrum output by the double-pass forward light path.
5. The novel high power stable ASE light source structure according to claim 4, characterized in that: The filter isolator is a double-stage optical isolator.
6. The novel high power stable ASE light source structure according to claim 5, characterized in that: The light source driving and temperature control circuit comprises a TEC driving and a laser driving, and the TEC driving adopts an integrated control chip MAX1978.