Broadband wavelength meter based on multi-stage fizeau interferometer

Abstract

The application discloses a wide-band wavelength meter based on a multi-stage Fizeau interference cavity, which comprises a fiber port, a concave mirror, a first mirror, a Fizeau single-stage cavity, a first cylindrical lens and a first linear array detector which are coaxially arranged along a first sub-light path in sequence, and a second mirror, a Fizeau multi-stage cavity, a second cylindrical lens and a second linear array detector which are coaxially arranged along a second sub-light path in sequence. The light emitted by the fiber port becomes parallel light after passing through the concave mirror, and then enters the Fizeau single-stage cavity and the Fizeau multi-stage cavity to interfere after passing through the first mirror and the second mirror respectively. The light emitted from the back bottom surface of the interference cavity converges energy through the first cylindrical lens and the second cylindrical lens and then forms interference fringes on the first linear array detector and the second linear array detector. Compared with a traditional wavelength measurement system, the application has a simpler and more stable structure, and can realize wide-band wavelength high-precision measurement through partition coating.

Description

Technical Field

[0001] This invention belongs to the field of optical precision measurement technology, and in particular to a wide-band wavelength meter based on a multi-level Fizeau interferometer cavity. Background Technology

[0002] With the development of laser technology, especially the use of tunable lasers and various new types of lasers, the wavelengths of laser sources have increased rapidly, and the wavelength range has become increasingly wider. Laser waves are important parameters in precision machining, precision mechanical manufacturing, and microelectronics. Accurate wavelength measurement not only ensures measurement accuracy but is also a key technology for traceability. Therefore, it is essential to develop high-precision, high-resolution, and wide-spectrum laser wavelength meters. Multibeam Fizeau interferometers can quickly and efficiently achieve wavelength measurement across a wide wavelength range with extremely high accuracy. Domestic research on wavelength measurement devices based on multibeam Fizeau interferometers is still in its early stages and urgently needs further in-depth study. Furthermore, due to limitations in coating processes, it is impossible to simultaneously achieve high-precision measurements of wavelengths across the ultraviolet, visible, and near-infrared wavelength ranges within the same interferometer cavity. Summary of the Invention

[0003] The purpose of this invention is to address the problems existing in the prior art by providing a wide-band wavelength meter based on a multi-level Fizeau interferometer cavity, enabling rapid and high-precision measurement of laser wavelengths within a wide band (192-1100nm).

[0004] The technical solution to achieve the purpose of this invention is as follows: a wideband wavelength meter based on a multi-stage Fizeau interferometer, characterized in that the wideband wavelength meter includes an optical fiber port and a concave mirror arranged coaxially along the main optical path; a first plane mirror, a Fizeau single-stage cavity, a first cylindrical mirror, and a first linear array detector arranged coaxially along the first sub-optical path; and a second plane mirror, a Fizeau multi-stage cavity, a second cylindrical mirror, and a second linear array detector arranged coaxially along the second sub-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 concave reflector and is then incident as parallel light onto the first and second reflectors. In the first sub-optical path, the parallel light is reflected by the first reflector and then incident into the Fizeau single-stage cavity, where it interferes. After exiting from the bottom surface of the Fizeau single-stage cavity, it is focused by the first cylindrical mirror onto the first linear array detector. In the second sub-optical path, the parallel light is reflected by the second reflector and then incident into the Fizeau multi-stage cavity, where it interferes. After exiting from the bottom surface of the Fizeau multi-stage cavity, it is focused by the second cylindrical mirror onto the second linear array detector.

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

[0007] Furthermore, the Fizeau single-stage cavity includes a first substrate, a first hollow cylinder, and a first cover plate that are sequentially arranged and bonded together along the first sub-optical path; the rear bottom surface of the first substrate is coated with a partially reflective and partially transmissive film; and the front bottom surface of the first cover plate is coated with a partially reflective and partially transmissive film.

[0008] Furthermore, the Fizeau multi-level cavity includes a second substrate, a second hollow cylinder, and a second cover plate that are sequentially arranged and bonded along the second sub-optical path. A step mirror is provided inside the second hollow cylinder. The rear bottom surface of the second substrate is bonded to the front bottom surface of the step mirror. A partially reflective and partially transmissive film is deposited on the rear bottom surface of the step mirror. A partially reflective and partially transmissive film is deposited on the front bottom surface of the second cover plate.

[0009] Compared with the prior art, the present invention has the following significant advantages:

[0010] (1) Compared with traditional wavelength measurement systems, the optical path is simpler and no reference laser is required.

[0011] (2) The high accuracy of the measurement results can be guaranteed by the dual-cavity multi-stage structure.

[0012] (3) Wide-band wavelength high-precision measurement can be achieved through partitioned coating.

[0013] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the wideband wavelength meter based on a multi-stage Fizeau interferometer cavity of the present invention.

[0015] Figure 2 This is a schematic diagram of the Fizeau single-stage cavity structure of the present invention.

[0016] Figure 3 This is a schematic diagram of the Fizeau multi-level cavity structure of the present invention. Detailed Implementation

[0017] 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.

[0018] 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.

[0019] 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.

[0020] In one embodiment, combined Figure 1 A wideband wavelength meter based on a multi-stage Fizeau interferometer is proposed. The wideband wavelength meter includes an optical fiber port 1 and a concave mirror 2 arranged coaxially along the main optical path; a first plane mirror 3, a Fizeau single-stage cavity 4, a first cylindrical mirror 5, and a first linear array detector 6 arranged coaxially along the first sub-optical path; and a second plane mirror 7, a Fizeau multi-stage cavity 8, a second cylindrical mirror 9, and a second linear array detector 10 arranged coaxially along the second sub-optical path. All optical elements are coaxial and at the same height relative to the instrument base plane.

[0021] The light emitted from fiber port 1 passes through concave reflector 2 and is incident as parallel light on first reflector 3 and second reflector 7. In the first sub-optical path, the parallel light is reflected by first reflector 3 and then incident on Fizeau single-stage cavity 4, where it interferes. After exiting from the bottom surface of Fizeau single-stage cavity 4, it is focused by first cylindrical mirror 5 onto first linear array detector 6. In the second sub-optical path, the parallel light is reflected by second reflector 7 and then incident on Fizeau multi-stage cavity 8, where it interferes. After exiting from the bottom surface of Fizeau multi-stage cavity 8, it is focused by second cylindrical mirror 9 onto second linear array detector 10.

[0022] Furthermore, in one embodiment, the fiber optic port 1 is located at the focal point of the concave reflector 2.

[0023] Furthermore, in one embodiment, combined with Figure 2 The Fizeau single-stage cavity 4 includes a first substrate 41, a first hollow cylinder 42, and a first cover plate 43, which are sequentially arranged and bonded along the first sub-optical path direction; the rear bottom surface of the first substrate 41 is coated with a partially reflective and partially transmissive film; the front bottom surface of the first cover plate 43 is coated with a partially reflective and partially transmissive film.

[0024] Furthermore, in one embodiment, the front and rear bottom surfaces of the first hollow cylinder 42 have a certain included angle.

[0025] Furthermore, in one embodiment, combined with Figure 3 The Fizeau multi-stage cavity 8 includes a second substrate 81, a second hollow cylinder 83, and a second cover plate 84, which are sequentially arranged and bonded along the second sub-optical path. A step mirror 82 is provided inside the second hollow cylinder 83. The rear bottom surface of the second substrate 81 is bonded to the front bottom surface of the step mirror 82. The rear bottom surface of the step mirror 82 is coated with a partially reflective and partially transmissive film. The front bottom surface of the second cover plate 84 is coated with a partially reflective and partially transmissive film.

[0026] Furthermore, in one embodiment, the front and rear bottom surfaces of the second hollow cylinder 83 have a certain included angle.

[0027] Furthermore, in one embodiment, the stepped mirror 82 includes a first to a fourth stepped section stacked from top to bottom, each step having a rectangular cross-section, the side of the rectangle along the cross-sectional direction of the beam being the short side and the side along the beam direction being the long side, and the short side of each step being bonded to the second substrate 81.

[0028] Furthermore, in one embodiment, the widths of the first to fourth steps are the same, and the lengths of the first to fourth steps increase sequentially.

[0029] 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 broadband wavelength meter based on a multi-stage Fizeau interferometer cavity, characterized in that, The wideband wavelength meter includes an optical fiber port (1) and a concave mirror (2) arranged coaxially along the main optical path; a first plane mirror (3), a Fizeau single-stage cavity (4), a first cylindrical mirror (5), and a first linear array detector (6) arranged coaxially along the first sub-optical path; and a second plane mirror (7), a Fizeau multi-stage cavity (8), a second cylindrical mirror (9), and a second linear array detector (10) arranged coaxially along the second sub-optical path; all optical elements are coaxial and at the same height relative to the instrument base plane. The light emitted from the fiber optic port (1) is reflected by the concave mirror (2) and then incident as parallel light onto the first plane mirror (3) and the second plane mirror (7). In the first sub-optical path, the parallel light is reflected by the first plane mirror (3) and then incident into the Fizeau single-stage cavity (4) where it interferes. After that, it exits from the bottom surface of the Fizeau single-stage cavity (4) and is focused by the first cylindrical mirror (5) onto the first linear array detector (6). In the second sub-optical path, the parallel light is reflected by the second plane mirror (7) and then incident into the Fizeau multi-stage cavity (8) where it interferes. After that, it exits from the bottom surface of the Fizeau multi-stage cavity (8) and is focused by the second cylindrical mirror (9) onto the second linear array detector (10). The Fizeau single-stage cavity (4) includes a first substrate (41), a first hollow cylinder (42) and a first cover plate (43) arranged and bonded together in sequence along the first sub-optical path; the rear bottom surface of the first substrate (41) is coated with a partially reflective and partially transmissive film; the front bottom surface of the first cover plate (43) is coated with a partially reflective and partially transmissive film. The Fizeau multi-stage cavity (8) includes a second substrate (81), a second hollow cylinder (83), and a second cover plate (84) arranged and bonded together in sequence along the second sub-optical path. A step mirror (82) is provided inside the second hollow cylinder (83). The rear bottom surface of the second substrate (81) is bonded to the front bottom surface of the step mirror (82). The rear bottom surface of the step mirror (82) is coated with a partially reflective and partially transmissive film. The front bottom surface of the second cover plate (84) is coated with a partially reflective and partially transmissive film. The stepped mirror (82) includes a first step to a fourth step stacked from top to bottom. The cross-section of each step is rectangular. The side of the rectangle along the cross-section direction of the beam is the short side, and the side along the beam direction is the long side. The short side of each step is glued to the second substrate (81). The width of the first step to the fourth step is the same, and the length of the first step to the fourth step increases sequentially.

2. The broadband wavelength meter based on a multi-stage Fizeau interferometer cavity according to claim 1, characterized in that, The fiber optic port (1) is located at the focal point of the concave reflector (2).

3. The broadband wavelength meter based on a multi-stage Fizeau interferometer cavity according to claim 1, characterized in that, The front and rear bottom surfaces of the first hollow cylinder (42) have a certain angle.

4. The broadband wavelength meter based on a multi-stage Fizeau interferometer cavity according to claim 1, characterized in that, The front and rear bottom surfaces of the second hollow cylinder (83) have a certain angle.

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