Notch filter adjusting structure

Abstract

The utility model discloses a notch filter adjusting structure which comprises an optical sleeve, a filter is coaxially installed in the optical sleeve in a sliding fit mode, a knob is arranged on the outer side of the optical sleeve, a rotary adapter is installed on the end portion of the knob, the rotary adapter is connected with the filter in a matched mode, and the filter can be adjusted by rotating the knob. And the filter can be driven to move along the axial direction of the optical sleeve by rotating the adapter. The device is simple in structure and convenient to adjust, and the signal-to-noise ratio and the detection precision of the two-photon absorption spectrum are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of optical equipment, in particular to a notch filter adjustment structure. Background Art

[0002] Two-photon absorption (TPA) has become an important method for measuring high-precision atomic spectra (including atomic hyperfine structure and isotope shift). TPA allows electrons outside the nucleus to absorb photon energy and transition to energy levels comparable to those achieved by single-photon transitions. This energy is then de-excited to emit fluorescence of a specific wavelength. The number of fluorescence photons is detected by a PMT, which in turn infers the intensity of the TPA spectrum. This provides an experimental basis for the measurement of atomic hyperfine spectra and isotope shift absorption spectra.

[0003] Since two-photon absorption has a very low yield, the number of measured fluorescence photons is very small, and the ambient stray light has a great impact on the signal-to-noise ratio of the detection light. At the same time, during the fluorescence spectrum collection process, there are different angles of incidence such as sputtering and scattering of fluorescence photons. However, in the current fluorescence spectrum collection equipment, it is difficult to collect sputtered and scattered photons, and the filter is generally fixed and difficult to adjust to the optimal filtering position, resulting in a low signal-to-noise ratio of the two-photon absorption spectrum and poor measurement accuracy. Utility Model Content

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a notch filter adjustment structure to solve the problems of low signal-to-noise ratio and poor measurement accuracy of the absorption spectrum in the prior art.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a notch filter adjustment structure, including an optical sleeve, in which a filter is slidably fitted and coaxially installed, and a sealing ring is provided between the filter and the sleeve; a knob is provided on the outside of the optical sleeve, and a rotary adapter is installed at one end of the knob close to the optical sleeve, and the rotary adapter is connected to the filter. By rotating the knob, the filter can be driven to move axially along the optical sleeve through the rotary adapter.

[0006] As an optimization, the rotary adapter includes a turntable, the axis of which coincides with the axis of the knob and is perpendicular to the axis of the optical sleeve. A driving gear coaxial with the turntable is provided on the side of the turntable close to the filter, a spiral groove is provided around the circumferential surface of the filter, and a tooth groove matching the driving gear is provided on the upper side or lower side of the groove. The driving gear extends into the spiral groove and engages with the tooth groove; the turntable rotates under the drive of the knob, and can drive the filter to move along the axis of the optical sleeve through the driving gear.

[0007] As an optimization, the rotary adapter includes a bracket installed on one side of the optical sleeve, and an intermediate gear is rotatably installed on the bracket, wherein the circumferential side of the intermediate gear is provided with a thread, and correspondingly, a matching thread is provided around the circumferential surface of the filter, and one side of the intermediate gear extends into the optical sleeve and engages with the filter; a turntable is installed at the end of the knob close to the optical sleeve, the axis of the turntable coincides with the axis of the knob and is perpendicular to the axis of the optical sleeve, and bevel teeth are provided around the turntable on the side of the turntable close to the optical sleeve, and correspondingly, bevel teeth are provided around the turntable and matching with the turntable at the end of the intermediate gear. By turning the knob, the turntable can drive the intermediate gear to rotate around its axis, thereby driving the filter to move along the axis of the optical sleeve.

[0008] As an optimization, a transmission clamping ring is sleeved on the middle part of the filter, and the spiral groove or thread is provided on the transmission clamping ring.

[0009] As an optimization, there are two sealing rubber rings, which are distributed on the upper and lower optical sleeves of the transmission clamping ring.

[0010] As an optimization, a photomultiplier tube is provided at one end of the optical sleeve, and the other end is an open end, and a target chamber is provided at the open end. A concave reflector is provided on the side of the target chamber away from the optical sleeve, and the focus of the concave reflector is located in the optical sleeve and on the side of the filter close to the photomultiplier tube.

[0011] Compared with the existing technology, the utility model has the following advantages: by using an optical sleeve to confine photons in a closed space formed by the optical sleeve, and the position of the filter in the optical sleeve can be conveniently adjusted by a knob and a rotary adapter, so that the filter can be adjusted to the optimal position, thereby obtaining the optimal two-photon absorption spectrum signal-to-noise ratio, improving measurement accuracy, and greatly improving the hyperfine structure and isotope shift resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic structural diagram of Example 1 of the present utility model;

[0013] Figure 2 This is a schematic structural diagram of Example 2 of the present utility model;

[0014] In the figure: 1 optical sleeve, 2 filter, 3 knob, 4 turntable, 5 drive gear, 6 spiral groove, 7 photomultiplier tube, 8 target chamber, 9 laser beam, 10 concave reflector, 11 intermediate gear, 12 drive retaining ring, 13 sealing rubber ring, 14 bracket DETAILED DESCRIPTION

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the utility model for protection, but merely represents the selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0017] It should be noted that similar reference numerals and letters denote similar items in the following figures. Therefore, once an item is defined in one figure, it does not require further definition or explanation in subsequent figures. In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the figures, or the orientations or positional relationships in which the inventive product is typically placed when in use. These terms are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation, and are therefore not to be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third," etc., are used solely to distinguish descriptions and are not to be construed as indicating or implying relative importance. Furthermore, terms such as "horizontal" and "vertical" do not imply that a component must be absolutely horizontal or overhanging, but rather may be slightly tilted. For example, "horizontal" simply refers to a direction that is more horizontal than "vertical," and does not imply that the structure must be completely horizontal, but rather may be slightly tilted. In the description of the present invention, it should also be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to mechanical connections or electrical connections; they may refer to direct connections or indirect connections through an intermediate medium; and they may refer to internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0018] Example 1: See Figure 1A notch filter adjustment structure includes an optical sleeve 1, one end of which is provided with a photomultiplier tube 7, and the other end is an open end, and a target chamber 8 is provided at the open end. The target chamber 8 is provided with a corresponding atomic structure or isotope or other substance. When in use, a laser beam 9 is irradiated in the target chamber 8, and a concave reflector 10 is provided on the side of the target chamber 8 away from the optical sleeve 1. In this way, the laser beam 9 passes through the target chamber 8, thereby exciting the atoms or isotopes to emit photons. The photons are reflected and focused by the concave reflector 10 and then enter the optical sleeve 1. After passing through the filter 2, they enter the photomultiplier. Through detection by the photomultiplier, the number of fluorescence photons is obtained, and the intensity of the two-photon absorption spectrum is reversely deduced, thereby obtaining the corresponding atomic spectrum data.

[0019] Specifically, a filter 2 (notch filter 2) is slidably fitted and coaxially mounted within an optical sleeve 1. A knob 3 is provided on the outside of the optical sleeve 1, and a rotary adapter is mounted on the end of the knob 3. The rotary adapter is coupled to the filter 2. By rotating the knob 3, the rotary adapter can be used to drive the filter 2 to move axially along the optical sleeve 1. By varying the axial position of the notch filter 2 within the optical sleeve 1, the signal-to-noise ratio of the resulting two-photon absorption spectrum can be improved, thereby significantly enhancing the hyperfine structure and isotope shift resolution.

[0020] Specifically, the rotary adapter includes a turntable 4, the axis of which coincides with the axis of the knob 3 and is perpendicular to the axis of the optical sleeve 1. A drive gear 5 coaxial with the turntable 4 is provided on the side of the turntable 4 near the filter 2. A spiral groove 6 is provided around the circumference of the filter 2, and a tooth groove that cooperates with the drive gear 5 is provided on the upper or lower side of the groove. The drive gear 5 extends into the spiral groove 6 and engages with the tooth groove. The turntable 4 rotates under the drive of the knob 3, and can drive the filter 2 to move along the axis of the optical sleeve 1 through the drive gear 5. The filter 2 can be installed in the optical sleeve 1 through a threaded fit. The turntable 4 drives the filter 2 to rotate about its axis through the engagement of the drive gear 5 with the tooth groove. During rotation, the turntable 4 moves along the axis of the optical sleeve 1 under the action of the thread, thereby adjusting the position of the filter 2. By adjusting the position of the filter 2, an optimal two-photon absorption spectroscopy signal-to-noise ratio is obtained.

[0021] A sealing rubber ring 13 is provided between the circumferential surface of the filter 2 and the wall of the optical sleeve 1 to enhance sealing, prevent photons from escaping from the sides, and further improve detection accuracy. Specifically, a transmission clasp 12 is sleeved in the middle of the filter 2, and the spiral groove 6 or thread is provided on the transmission clasp 12. There are two sealing rubber rings 13, distributed on the upper and lower sides of the optical sleeve 1 of the transmission clasp 12. This eliminates the need to machine the filter 2, ensuring its integrity. Specifically, the threads and spiral groove 6 on the transmission clasp 12 can be arranged in a cross-arrangement, with the spiral groove 6 meshing with the drive gear 5 and the threads meshing with the optical sleeve 1, thereby enabling the knob 3 to drive the filter 2 to rotate and simultaneously move along the axis of the optical sleeve 1.

[0022] Example 2, see Figure 2 , different from the first embodiment, the rotary adapter includes a bracket 14 installed on one side of the optical sleeve 1, and an intermediate gear 11 is rotatably mounted on the bracket 14, wherein the circumferential side of the intermediate gear 11 is provided with a thread, and correspondingly, a matching thread is provided around the circumferential surface of the filter 2, and one side of the intermediate gear 11 extends into the optical sleeve 1 and engages with the filter 2; a turntable 4 is installed at the end of the knob 3 close to the optical sleeve 1, and the axis of the turntable 4 coincides with the axis of the knob 3 and is perpendicular to the axis of the optical sleeve 1, and a bevel gear is provided around the turntable 4 on the side of the turntable 4 close to the optical sleeve 1, and correspondingly, a bevel gear is provided around the turntable 4 at the end of the intermediate gear 11, and by rotating the knob 3, the turntable 4 can drive the intermediate gear 11 to rotate around its axis, thereby driving the filter 2 to move along the axis of the optical sleeve 1. In this way, when working, the knob 3 is rotated, and the knob 3 drives the turntable 4 to rotate. The turntable 4 drives the intermediate gear 11 to rotate through the engagement of the bevel teeth. The intermediate gear 11 is coaxial with the filter 2 and is connected through threaded cooperation. Therefore, the rotation of the intermediate gear 11 can drive the filter 2 to move along the axis of the optical sleeve 1. During this process, the filter 2 only moves driven by the thread and does not rotate. Therefore, it is no longer necessary to have a threaded cooperation structure with the optical sleeve 1, thereby improving the installation flexibility of the filter 2.

[0023] The utility model uses an optical sleeve to confine photons in a closed space formed by the optical sleeve, and the position of the filter in the optical sleeve can be conveniently adjusted by a knob and a rotary adapter, so that the filter can be adjusted to the optimal position, thereby obtaining the optimal two-photon absorption spectrum signal-to-noise ratio, improving measurement accuracy, and greatly improving the hyperfine structure and isotope shift resolution.

[0024] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the technical solution. Ordinary technicians in this field should understand that those modifications or equivalent replacements of the technical solution of the present invention that do not depart from the purpose and scope of the technical solution of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A notch filter adjustment structure, characterized in that: It includes an optical sleeve, in which a filter is slidably fitted and coaxially installed, and a sealing rubber ring is provided between the filter and the sleeve; a knob is provided on the outside of the optical sleeve, and a rotary adapter is installed on one end of the knob close to the optical sleeve, and the rotary adapter is connected with the filter. By turning the knob, the filter can be driven to move axially along the optical sleeve through the rotary adapter.

2. The notch filter adjustment structure according to claim 1, characterized in that: The rotary adapter includes a turntable, the axis of which coincides with the axis of the knob and is perpendicular to the axis of the optical sleeve. A driving gear coaxial with the turntable is provided on the side of the turntable close to the filter. A spiral groove is provided around the circumferential surface of the filter, and a tooth groove matching the driving gear is provided on the upper side or lower side of the groove. The driving gear extends into the spiral groove and engages with the tooth groove. The turntable rotates under the drive of the knob and can drive the filter to move along the axis of the optical sleeve through the driving gear.

3. The notch filter adjustment structure according to claim 1, wherein: The rotary adapter includes a bracket installed on one side of the optical sleeve, and an intermediate gear is rotatably installed on the bracket, wherein the circumferential side of the intermediate gear is provided with a thread, and correspondingly, a matching thread is provided around the circumferential surface of the filter, and one side of the intermediate gear extends into the optical sleeve and engages with the filter; a turntable is installed at the end of the knob close to the optical sleeve, the axis of the turntable coincides with the axis of the knob and is perpendicular to the axis of the optical sleeve, and a side of the turntable close to the optical sleeve is provided with bevel teeth around the turntable, and correspondingly, a bevel tooth around the turntable and matching with the turntable is provided at the end of the intermediate gear. By rotating the knob, the turntable can drive the intermediate gear to rotate around its axis, thereby driving the filter to move along the axis of the optical sleeve.

4. The notch filter adjustment structure according to claim 2, wherein: A transmission clamping ring is sleeved on the middle part of the filter plate, and the spiral groove or thread is arranged on the transmission clamping ring.

5. The notch filter adjustment structure according to claim 4, characterized in that: There are two sealing rubber rings, which are distributed on the upper and lower optical sleeves of the transmission clamping ring.

6. The notch filter adjustment structure according to claim 1, characterized in that: A photomultiplier tube is provided at one end of the optical sleeve, and the other end is an open end. A target chamber is provided at the open end. A concave reflector is provided on the side of the target chamber facing away from the optical sleeve. The focus of the concave reflector is located in the optical sleeve and on the side of the filter close to the photomultiplier tube.

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