Single-channel multi-stage fizeau wavelength measuring device

Abstract

This invention discloses a single-channel multi-level Fizeau wavelength measurement device, comprising an optical fiber port, a collimating mirror, an interference cavity, a cylindrical mirror, and a linear array detector arranged coaxially along the main optical path. The laser to be measured is incident on the wavelength meter through the optical fiber port, collimated by the collimating mirror, and then incident on the Fizeau interference cavity for interference. The laser exits from the rear face of the interference cavity, and after being focused by the cylindrical mirror, interference fringes are formed in the linear array detector. Compared with traditional wavelength measurement systems, the single-channel multi-level Fizeau wavelength measurement device proposed in this invention has a simpler and more stable structure, and can achieve high-precision single-cavity wavelength measurement through partitioned coating.

Description

Technical Field

[0001] This invention relates to the field of optical precision measurement technology, and in particular to a single-channel multi-level Fizeau wavelength measurement device. Background Technology

[0002] Laser wavelength, as a measurement reference value, has been widely used in the measurement of displacement, flatness, roughness, vibration, gravitational acceleration, length, velocity, angle, straightness, and perpendicularity. Accurate wavelength measurement not only ensures measurement accuracy but is also a key technology for traceability. Furthermore, laser wavelength measurement has wide applications in atmospheric monitoring. Atmospheric wind speed can be measured by combining the wavelength drift of scattered laser light with the Doppler effect; this research has applications in astronomy and defense. Therefore, the development of high-precision, high-resolution, and wide-spectrum laser wavelength meters is essential. Traditional Michelson and FP interferometer wavelength meters have low measurement accuracy and can only be used for continuous laser measurements. Multibeam Fizeau interferometers can quickly and efficiently achieve high-precision measurement of wavelength and atmospheric wind speed. Domestic research on wavelength measurement devices based on multibeam Fizeau interferometers is still in its early stages and urgently needs further in-depth study. At the same time, existing wavelength measurement devices require multiple interferometer cavities, resulting in complex optical paths and low energy utilization. Summary of the Invention

[0003] The purpose of this invention is to provide a single-channel multi-stage Fizeau wavelength measurement device to address the problems existing in the prior art.

[0004] The technical solution to achieve the purpose of this invention is as follows: a single-channel multi-level Fizeau wavelength measurement device, wherein the single-cavity wavelength meter includes an optical fiber port, a collimating lens, a Fizeau interferometer cavity, a cylindrical mirror and a linear array detector arranged coaxially along the main optical path; all optical elements are coaxial and at the same height relative to the instrument base plane;

[0005] The light emitted from the fiber optic port passes through a collimating lens and is incident as parallel light into the Fizeau interference cavity, where it interferes. Then, it exits from the bottom rear surface of the Fizeau interference cavity and is focused by a cylindrical mirror onto a linear array detector to form interference fringes.

[0006] Furthermore, the fiber optic port is located at the focal point of the collimating lens.

[0007] Furthermore, the Fizeau interference cavity includes a substrate, a hollow cylinder, and a cover plate that are sequentially placed and glued together along the optical path direction. A stepped block is provided inside the hollow cylinder. The rear bottom surface of the substrate is glued to the front bottom surface of the stepped block. The rear bottom surface of the stepped block is coated with a partially reflective and partially transmissive film. The front bottom surface of the cover plate is coated with a partially reflective and partially transmissive film.

[0008] Compared with the prior art, the significant advantages of this invention are:

[0009] (1) Single-channel optical path, high energy utilization, and simple assembly and adjustment;

[0010] (2) High-precision measurement is achieved by using multi-stage Fizeau cavity iteration without the need for a reference laser;

[0011] (2) High-precision measurement of wide-band wavelengths can be achieved through partitioned coating.

[0012] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the single-channel multi-stage Fizeau wavelength measurement device of the present invention.

[0014] Figure 2 This is a schematic diagram of the Fizeau interference cavity structure of the present invention, wherein Figure (a) is the front view and Figure (b) is the side view. Detailed Implementation

[0015] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0016] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0017] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0018] In one embodiment, a single-channel multi-stage Fizeau wavelength measurement device is proposed, wherein the single-cavity wavelength meter includes an optical fiber port 1, a collimating mirror 2, a Fizeau interferometer cavity 3, a cylindrical mirror 4, and a linear array detector 5, which are placed coaxially along the main optical path; all optical elements are coaxial and at the same height relative to the instrument base plane.

[0019] The laser to be tested is incident on the wavelength meter through fiber port 1. The light emitted from fiber port 1 passes through collimating lens 2 and is incident as parallel light into Fizeau interference cavity 3, where it interferes. Then, it exits from the bottom surface of Fizeau interference cavity 3 and is focused by cylindrical lens 4 onto linear array detector 5.

[0020] Furthermore, in one embodiment, the fiber optic port 1 is located at the focal point of the collimating lens 2.

[0021] Furthermore, in one embodiment, the Fizeau interference cavity 3 includes a substrate 31, a hollow cylinder 32, and a cover plate 33 that are sequentially placed and glued along the optical path direction. The hollow cylinder 32 has a stepped block inside. The rear bottom surface of the substrate 31 is glued to the front bottom surface of the stepped block (the front and rear settings are set along the optical path direction). The rear bottom surface of the stepped block is coated with a partially reflective and partially transmissive film. The front bottom surface of the cover plate 33 is coated with a partially reflective and partially transmissive film.

[0022] Furthermore, in one embodiment, the front and rear bottom surfaces of the stepped block have a certain included angle.

[0023] Furthermore, in one embodiment, the stepped block includes a first step 34, a second step 35, and a third step 36 stacked sequentially from top to bottom. The cross-section of the three steps is rectangular, with the shorter side of the rectangle along the cross-sectional direction of the light beam. The longer sides of the three steps are bonded to the substrate 31.

[0024] Furthermore, in one embodiment, the first step 34, the second step 35, and the third step 36 have the same length, and the width of the first step 34 is twice the width of the second step 35 and the third step 36.

[0025] The single-channel multi-level Fizeau wavelength measurement device proposed in this invention has a simpler and more stable structure compared to traditional wavelength measurement systems, and can achieve high-precision single-cavity wavelength measurement through partitioned coating.

[0026] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention without departing from its spirit and scope should be included within the protection scope of the present invention.

Claims

1. A single-channel multi-stage Fizeau wavelength measurement device, characterized in that, The single-cavity wavelength meter includes an optical fiber port (1), a collimating mirror (2), a Fizeau interference cavity (3), a cylindrical mirror (4), and a linear array detector (5) arranged coaxially along the main optical path; all optical components are coaxial and at the same height relative to the instrument base plane. The light emitted from the fiber optic port (1) passes through the collimating lens (2) and is incident as parallel light into the Fizeau interferometer cavity (3) to cause interference. Then, it exits from the bottom surface of the Fizeau interferometer cavity (3) and is focused by the cylindrical mirror (4) onto the linear array detector (5). The Fizeau interference cavity (3) includes a substrate (31), a hollow cylinder (32), and a cover plate (33) that are placed and glued together along the optical path. The hollow cylinder (32) has a stepped block inside. The rear bottom surface of the substrate (31) is glued to the front bottom surface of the stepped block. The rear bottom surface of the stepped block is coated with a partially reflective and partially transmissive film. The front bottom surface of the cover plate (33) is coated with a partially reflective and partially transmissive film. There is a certain included angle between the front and rear bottom surfaces of the stepped block; The stepped block includes a first step (34), a second step (35) and a third step (36) stacked from top to bottom. The cross-section of the three steps is rectangular, and the side of the rectangle along the cross-sectional direction of the beam is the short side. The long side of the three steps is glued to the substrate (31). The first step (34), the second step (35) and the third step (36) have the same length, and the width of the first step (34) is twice the width of the second step (35) and the third step (36).

2. The single-channel multi-stage Fizeau wavelength measurement device according to claim 1, characterized in that, The fiber optic port (1) is located at the focal point of the collimating lens (2).

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