A method and apparatus for measuring the frequency of rotation of the head of a sperm

Abstract

The present application relates to sperm movement technical field, especially a kind of method and device for measuring sperm head rotation frequency, comprising: S1, the image information of sample to be measured is obtained, based on the image information, select target sperm;S2, based on the target sperm, the light spot of the target sperm head after the target sperm is captured to head in the preset optical tweezers light beam is obtained;S3, based on the light spot of the target sperm head, the light spot intensity variation information is obtained, the light spot intensity variation information is converted into electrical signal data, the electrical signal data is carried out power spectrum analysis, and the rotation frequency of the target sperm head is obtained.The present application carries out real-time monitoring and analysis to sperm movement characteristics, can quickly obtain sperm movement characteristics, and the accuracy of measurement result is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sperm motility, in particular to a method and device for measuring the rotation frequency of sperm heads. BACKGROUND

[0002] In the process of sperm fertilization, the movement mode of sperm is crucial for successful fertilization. The movement of sperm is driven by its flagellum, and the human sperm flagellum rotates and swings around its long sleeve. This rotational swing not only drives the forward movement of the sperm, but also causes the rotation of the sperm head, making the sperm advance in a spiral shape. Therefore, the motility of sperm and the rotation frequency of the head are closely related, both of which are derived from the movement of the flagellum.

[0003] The spiral movement of the sperm head may be one of the keys to the successful completion of sperm fertilization. By measuring the rotation frequency of the sperm head, the level of sperm motility and the prediction of fertilization potential can be objectively evaluated, providing an important reference for reproductive medicine and biological research. The application of optical tweezer technology in the field of reproduction provides an effective means for the analysis of sperm head movement. Optical tweezers can capture and control the position of the sperm head using a laser beam, making it possible to continuously obtain and analyze images of the sperm head, thereby obtaining the movement information of the sperm head.

[0004] However, after capturing the sperm head with optical tweezers, it mainly relies on continuous image analysis. This method usually requires high-resolution microscopes and complex image processing systems to analyze the rapid rotation of the sperm head. However, the results of image analysis may be affected by complex background noise, thereby reducing the measurement accuracy. At the same time, image processing usually requires post-processing, which not only increases the processing time, but also leads to poor real-time performance, which cannot meet the real-time monitoring requirements of sperm movement characteristics.

[0005] Secondly, some studies attempt to combine optical tweezer technology and deep learning algorithms to measure the rotation frequency of the sperm head through image analysis. Although deep learning performs well in image processing, this method requires a large amount of training data and high computing resources, and the accuracy of image analysis is still limited by the quality of the image and the amount of training samples. In addition, the complexity and high computing demand of deep learning algorithms further increase the cost and operation difficulty of the system, which limits its practical application.

[0006] Therefore, there is an urgent need for a method and device for measuring the rotation frequency of the sperm head. SUMMARY

[0007] (I) Technical problems to be solved

[0008] In view of the above-mentioned defects and disadvantages of the prior art, the present application provides a method and device for measuring the rotation frequency of sperm head, which solves the technical problems of poor real-time performance, high calculation requirement, dependence on post-processing and large operation difficulty in the prior art.

[0009] (II) Technical solutions

[0010] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the present application include:

[0011] The embodiment of the present application provides a method for measuring the rotation frequency of sperm head, comprising:

[0012] S1, obtaining image information of a sample to be measured, and selecting a target sperm based on the image information;

[0013] S2, obtaining a light spot of the head of the target sperm after the head of the target sperm is captured in a preset optical tweezer light beam based on the target sperm;

[0014] S3, obtaining light spot intensity change information based on the light spot of the head of the target sperm, converting the light spot intensity change information into electrical signal data, performing power spectrum analysis on the electrical signal data, and obtaining the rotation frequency of the head of the target sperm.

[0015] Optionally, the S2 comprises:

[0016] Based on the target sperm, the head of the target sperm is captured using a first laser, and at the same time, a second laser is used to irradiate the head of the target sperm to form a light spot of the head of the target sperm.

[0017] Optionally, the first laser and the second laser are lasers with a wavelength range of 400 nanometers to 1100 nanometers.

[0018] In a second aspect, the embodiment of the present application provides a device for measuring the rotation frequency of sperm head, comprising:

[0019] An optical tweezer assembly, a light spot forming assembly, a sample pool, and a position sensitive detector assembly;

[0020] The sample pool is used for placing a sample to be measured;

[0021] The optical tweezer assembly is used for capturing the head of a target sperm in the sample to be measured in the sample pool;

[0022] The light spot forming assembly is used for forming a light spot of the head of the target sperm captured by the optical tweezer assembly;

[0023] The position sensitive detector assembly is used to receive the light spot of the target sperm head formed by the light spot forming assembly, obtain light spot intensity change information, convert the light spot intensity change information into electrical signal data, perform power spectrum analysis on the electrical signal data, and obtain the rotation frequency of the target sperm head.

[0024] Optionally, the optical tweezers assembly comprises a first laser, and a lens for expanding the laser beam;

[0025] The first laser emits first laser light, which is transmitted through the first dichroic mirror in the position sensitive detector assembly after being expanded by the lens, and then passes through the objective lens OBJ to manipulate and position the head of the target sperm in the sample cell.

[0026] Optionally, the lens for expanding the laser beam comprises a first lens and a second lens, and the first lens and the second lens are used to expand the laser beam emitted by the first laser.

[0027] Optionally, the light spot forming assembly comprises:

[0028] a second laser, a second dichroic mirror, a first mirror, and a condenser CON;

[0029] The second laser emits second laser light, which is reflected by the second dichroic mirror and the first mirror and then condensed by the condenser CON to the head region of the target sperm in the sample cell, forming a light spot corresponding to the rotation of the target sperm head.

[0030] Optionally, the light spot forming assembly further comprises:

[0031] an LED light source for providing illumination and a third lens;

[0032] The LED light source emits illumination light, which passes through the third lens and the second dichroic mirror, the first mirror, and the condenser CON of the light spot forming assembly to illuminate the sample cell.

[0033] Optionally, the position sensitive detector assembly comprises:

[0034] an objective lens OBJ, a first dichroic mirror, a third dichroic mirror, a fifth lens for expanding, a position sensitive detector, a data acquisition card, and a computer;

[0035] The position sensitive detector receives the light beam that passes through the objective lens OBJ and is reflected by the first dichroic mirror and the third dichroic mirror in the sample cell, focuses the light beam through the fifth lens to transmit the light spot intensity change information of the target sperm head, converts the light spot intensity change information into electrical signal data and sends it to the data acquisition card, and the data acquisition card sends the electrical signal data to the computer;

[0036] The computer receives the electric signal data, performs power spectrum analysis on the electric signal data, and obtains the rotation frequency of the target sperm head.

[0037] Optionally, the device further comprises:

[0038] An imaging acquisition component is configured to acquire image information of a sample in a sample pool, and select a target sperm based on the image information.

[0039] The imaging acquisition component comprises a camera and a fourth lens.

[0040] After the light beam in the sample pool is transmitted through the objective lens OBJ in the position sensitive detector component, reflected by the first dichroic mirror, and then transmitted through the third dichroic mirror, the light beam is transmitted to the camera through the fourth lens to generate image information in the sample pool.

[0041] (III) Beneficial Effects

[0042] The method and device for measuring the rotation frequency of the sperm head have the advantages that the position sensitive detector is used to detect the change of the light spot position in real time, the sperm movement characteristics can be monitored and analyzed in real time, the sperm movement characteristics can be quickly acquired, and accurate measurement results can be provided, so that high-frequency information in the sperm rotation process can be captured, the sperm movement mode can be analyzed in depth, the device is simple in design, practical and economical, the cost and operation difficulty are reduced, and the device is easy to operate. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 FIG. 1 is a schematic diagram of a method for measuring the rotation frequency of the sperm head according to the present application;

[0044] Figure 2 FIG. 2 is a schematic diagram of a device for measuring the rotation frequency of the sperm head according to the present application;

[0045] Figure 3 FIG. 3 is a schematic diagram of the light tweezers capturing the sperm in the embodiment 3 of the present application;

[0046] Figure 4 FIG. 4 is a schematic diagram of the electric signal generated by the sperm head movement in the x direction and the y direction in the embodiment 3 of the present application;

[0047] Figure 5 FIG. 5 is a schematic diagram of the power spectrum density of the electric signal of the sperm head in the embodiment 3 of the present application.

[0048]

Explanation of Reference Signs

[0049] 1: first laser; 2: first lens; 3: second lens; 4: first dichroic mirror; 5: objective lens OBJ; 6: condenser CON; 7: first mirror; 8: second dichroic mirror; 9: third lens; 10: LED light source; 11: sample cell; 12: second laser; 13: third dichroic mirror; 14: fourth lens; 15: camera; 16: fifth lens; 17: position sensitive detector; 18: data acquisition card; 19: computer; 20: display screen. DETAILED DESCRIPTION

[0050] In order to better explain the present application, so as to be understood, the present application is described in detail below by specific embodiments, combined with the accompanying drawings.

[0051] The device for measuring the rotation frequency of the sperm head provided by the embodiment of the present application controls the position of the sperm head through optical tweezer technology, and simultaneously uses a position sensitive detector to monitor the change in the position of the light spot caused by the rotation of the sperm head in real time, thereby solving the problems of poor real-time performance, low measurement accuracy, dependence on post-processing and high computing requirements in the prior art. The present application can quickly obtain the motion characteristics of sperm, provide accurate measurement results, and provide reliable data support for reproductive medicine and biological research, promote in-depth research on the motion mechanism of sperm, and further provide an important reference for the diagnosis and treatment of infertility.

[0052] In order to better understand the above technical solutions, the exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided so that the present application can be more clearly, thoroughly understood, and the scope of the present application can be completely conveyed to those skilled in the art.

[0053] DETAILED DESCRIPTION

[0054] Embodiment 1

[0055] Referring to Figure 1 The method for measuring the rotation frequency of the sperm head provided by the embodiment of the present application comprises:

[0056] Step S1: obtaining image information of a sample to be measured, and selecting a target sperm based on the image information;

[0057] Step S2: obtaining a light spot of the head of the target sperm after the target sperm is captured to the head in a preset optical tweezer light beam based on the target sperm;

[0058] Step S3, based on the light spot of the target sperm head, obtaining light spot intensity variation information, converting the light spot intensity variation information into electrical signal data, performing power spectrum analysis on the electrical signal data, and obtaining the rotation frequency of the target sperm head.

[0059] In this embodiment, step S2 includes:

[0060] Based on the target sperm, the head of the target sperm is captured using a first laser, and a second laser is used to irradiate the head of the target sperm, forming a light spot of the target sperm head.

[0061] In a specific implementation process, the first laser and the second laser are lasers with a wavelength range of 400 nanometers to 1100 nanometers, and the power of the first laser is greater than the power of the second laser.

[0062] In this embodiment, the light spot of the target sperm head is formed by the optical tweezer technology, and the light spot intensity variation information of the target sperm head is obtained at the same time. The light spot of the target sperm head is obtained by processing the light spot intensity variation information, which can quickly obtain the sperm movement characteristics and provide accurate measurement results, thereby improving the measurement accuracy.

[0063] Embodiment 2

[0064] Referring to Figure 2 , a device for measuring the rotation frequency of a sperm head according to an embodiment of the present application includes:

[0065] The optical tweezer assembly, the light spot forming assembly, the sample pool 11, and the position sensitive detector assembly;

[0066] The sample pool 11 is used to place a sample to be measured;

[0067] The optical tweezer assembly is used to capture the head of a target sperm in the sample to be measured in the sample pool 11;

[0068] The light spot forming assembly is used to form a light spot of the head of the target sperm captured by the optical tweezer assembly;

[0069] The position sensitive detector assembly is used to receive the light spot of the head of the target sperm formed by the light spot forming assembly, obtain light spot intensity variation information, convert the light spot intensity variation information into electrical signal data, perform power spectrum analysis on the electrical signal data, and obtain the rotation frequency of the head of the target sperm.

[0070] In this embodiment, the sample to be measured placed in the sample pool 11 contains human sperm, and the head of the sperm is about several microns in diameter and has an ellipsoidal shape.

[0071] The device for measuring the rotation frequency of the sperm head of the embodiment can realize real-time monitoring by combining the optical tweezer assembly and the position sensitive detector assembly, the data processing process is simplified by performing power spectrum analysis on the electrical signal data, the complexity of data processing is greatly reduced, the demand for high computing resources is reduced, the cost of the device is reduced, and the device is more practical and economical.

[0072] Embodiment 3

[0073] The device for measuring the rotation frequency of the sperm head of the embodiment comprises:

[0074] The optical tweezer assembly, the light spot forming assembly, the sample cell 11 and the position sensitive detector assembly.

[0075] The sample cell 11 is used for placing the sample to be measured.

[0076] The optical tweezer assembly is used for capturing the head of the target sperm in the sample to be measured in the sample cell 11.

[0077] The light spot forming assembly is used for forming the light spot of the head of the target sperm captured by the optical tweezer assembly.

[0078] The position sensitive detector assembly is used for receiving the light spot of the head of the target sperm formed by the light spot forming assembly, acquiring the light spot intensity change information, converting the light spot intensity change information into electrical signal data, performing power spectrum analysis on the electrical signal data, and acquiring the rotation frequency of the head of the target sperm.

[0079] In the embodiment, the optical tweezer assembly comprises a first laser 1 and a lens for expanding the laser beam.

[0080] The first laser 1 emits first laser, and the first laser is transmitted through the first dichroic mirror 4 in the position sensitive detector assembly after being expanded by the lens, and then passes through the objective lens OBJ 5 to manipulate and position the head of the target sperm in the sample cell 11.

[0081] The lens for expanding the laser beam comprises a first lens 2 and a second lens 3, and the first lens 2 and the second lens 3 are used for expanding the laser beam emitted by the first laser 1.

[0082] In the embodiment, the wavelength range of the first laser emitted by the first laser 1 is 400 nanometers to 1100 nanometers.

[0083] For example, referring to Figure 3The first laser emitted from the first laser 1 firstly passes through the first lens 2 and the second lens 3 for beam expansion to increase the size of the light beam, and finally enters the objective lens OBJ 5 to form the optical tweezer in the sample cell 11. The sample cell 11 contains human sperm, and the head of the human sperm is about several microns in diameter and has an ellipsoidal shape. The optical tweezer in the sample cell 11 can capture and control the head of the sperm, so that the sperm can maintain a relatively stable position in the three-dimensional space.

[0084] In the specific implementation process, the light spot forming assembly comprises:

[0085] The second laser 12, the second dichroic mirror 8, the first mirror 7, and the condenser CON 6.

[0086] The second laser 12 emits the second laser, and the second laser passes through the second dichroic mirror 8 and the first mirror 7 and is then condensed by the condenser CON 6 to the head region of the target sperm in the sample cell 11, to form a light spot corresponding to the rotation of the head of the target sperm.

[0087] In the embodiment, the condenser CON 6 is coaxially arranged with the objective lens OBJ 5, the second dichroic mirror 8 is arranged at an angle of 45° based on the axis of the condenser CON 6, and the second dichroic mirror 8 is arranged at an angle of 45° based on the axis of the second laser 12.

[0088] The second laser 12 is a laser that emits a laser with a wavelength of 400-1100 nm, and the second laser 12 is a laser that is started at the same time as the first laser 1.

[0089] In the embodiment, the power of the first laser 1 is greater than the power of the second laser 12.

[0090] In the embodiment, the light spot forming assembly further comprises:

[0091] The LED light source 10 for providing illumination and the third lens 9.

[0092] The LED light source 10 emits illumination light, and the illumination light passes through the third lens 9 and the second dichroic mirror 8, the first mirror 7, and the condenser CON 6 of the light spot forming assembly to illuminate the sample cell 11.

[0093] In the embodiment, the LED light source 10 is coaxially arranged with the third lens 9, and the third lens 9 is used to focus the illumination light emitted by the LED light source. The angle between the axis of the third lens 9 and the axis of the second dichroic mirror 8 is 45°.

[0094] In the embodiment, the position sensitive detector detection assembly comprises:

[0095] an objective lens OBJ5, a first dichroic mirror 4, a third dichroic mirror 13, a fifth lens 16 for beam expansion, a position sensitive detector 17, a data acquisition card 18, and a computer 19;

[0096] The position sensitive detector 17 receives the light beam reflected by the first dichroic mirror 4 and the third dichroic mirror 13 after passing through the objective lens OBJ5 in the sample cell 11, and transmits the light spot intensity variation information of the target sperm head to the data acquisition card 18 after focusing by the fifth lens 16, and the data acquisition card 18 sends the electrical signal data to the computer 19.

[0097] In this embodiment, the position sensitive detector 17 has a light sensitive area and four electrodes, when the light spot irradiates on the light sensitive area, the photo-generated carriers move to the four electrodes, generating a current signal, and the position of the light spot on the x-axis and y-axis of the position sensitive detector 17 is determined by the intensity variation of the current signal. When the sperm head rotates, the intensity of the laser spot on the position sensitive detector 17 changes, resulting in periodic changes in the electrode electrical signal.

[0098] Referring to Figure 5 The computer 19 receives the electrical signal data, performs power spectrum analysis on the electrical signal data, and obtains the rotation frequency of the target sperm head.

[0099] In this embodiment, the data acquisition card 18 includes amplifiers, filters and other circuits for enhancing signals and eliminating noise.

[0100] In the specific implementation process, the objective lens OBJ5 is coaxially arranged with the sample cell 11, the first dichroic mirror 4 is arranged at an angle of 45° based on the axis of the objective lens OBJ5, the third dichroic mirror 13 is arranged at an angle of 180° based on the axis of the first dichroic mirror 4, the fifth lens 16 is coaxially arranged with the position sensitive detector 17, and the angle between the axis of the fifth lens 16 and the axis of the third dichroic mirror 13 is 45°.

[0101] In this embodiment, the computer 19 can also be a signal processing device for performing power spectrum analysis on the electrical signal data to obtain the rotation frequency of the target sperm head.

[0102] The device for measuring the rotation frequency of the sperm head in this embodiment further comprises:

[0103] An imaging acquisition assembly is configured to acquire image information of a sample to be measured in the sample cell 11, and select a target sperm based on the image information.

[0104] The imaging acquisition assembly comprises a camera 15 and a fourth lens 14.

[0105] The light beam in the sample cell 11 is transmitted through the objective lens OBJ5 in the position sensitive detector assembly, reflected by the first dichroic mirror 4, transmitted through the third dichroic mirror 13, transmitted to the camera 15 through the fourth lens 14, and the image information in the sample cell 11 is generated.

[0106] In the specific implementation process, the camera 15 acquires the image information of the sample in the sample cell 11, selects the target sperm according to the image information of the sample, and uses the optical tweezer assembly to control and position the target sperm.

[0107] The imaging acquisition assembly and the position sensitive detector assembly are integrated through the third dichroic mirror 13 in the position sensitive detector assembly.

[0108] In the specific implementation process, the camera 15 is a CCD camera, the camera 15 is coaxially arranged with the fourth lens 14, and the angle between the axis of the fourth lens 14 and the axis of the fifth lens 16 is 90°.

[0109] In the embodiment, the imaging acquisition assembly further includes a display screen 20, and the display screen 20 displays the image information in the sample cell 11 collected by the camera 15.

[0110] In the embodiment, the dichroic mirror is a lens capable of simultaneously projecting and reflecting; in order to reduce the size of the device and effectively and reasonably arrange the optical path, some components are shared.

[0111] The device for measuring the rotation frequency of the sperm head in the embodiment can control the sperm head by using the optical tweezer assembly, and can acquire the light spot intensity change information, i.e., the information of the rotation of the sperm head, by using the position sensitive detector assembly, so as to realize real-time monitoring and analysis of the motion characteristics of the sperm head, which helps to further analyze and understand the three-dimensional motion mode of the sperm; the computer is used to perform power spectrum analysis on the electrical signal data, which simplifies the data processing process, reduces the dependence on post-processing, greatly reduces the complexity of data processing, and greatly reduces the demand for high computing resources.

[0112] In the description of the present application, it should be understood that the terms "first", "second" are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0113] In the present application, unless specifically defined otherwise, the terms "mounting", "connected", "connection", "fixed", "unfixed", and the like should be construed broadly, for example, can be fixed connection, can be detachable connection, or integral; can be mechanical connection, can be electrical connection; can be direct connection, can be indirect connection through an intermediate medium; can be internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0114] In the present application, unless specifically defined otherwise, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature is "above", "over" and "on" the second feature, which can be directly above or obliquely above the first feature, or only indicates that the first feature is higher than the second feature in horizontal height. The first feature is "below", "under" and "under" the second feature, which can be directly below or obliquely below the first feature, or only indicates that the first feature is lower than the second feature in horizontal height.

[0115] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the present application and the features of the different embodiments or examples without contradiction.

[0116] Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can modify, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method of measuring the frequency of rotation of a sperm head, characterized by, The method comprises the following steps: S1, acquiring image information of a sample to be measured, and selecting a target sperm based on the image information; S2, based on the target sperm, acquiring a light spot of the head of the target sperm after the target sperm is captured to the head in a preset optical tweezer light beam; S3, based on the light spot of the head of the target sperm, acquiring light spot intensity change information, converting the light spot intensity change information into electrical signal data, performing power spectrum analysis on the electrical signal data, and acquiring the rotation frequency of the head of the target sperm.

2. The method of claim 1, wherein, The S2 comprises: Based on the target sperm, the head of the target sperm is captured by using a first laser, and a second laser is used to irradiate the head of the target sperm, thereby forming a light spot of the head of the target sperm.

3. The method of claim 2, wherein the first laser and the second laser are lasers with a wavelength ranging from 400 nm to 1100 nm. The device comprises:

4. An apparatus for measuring the frequency of rotation of the head of a spermatozoon, characterized in that, an optical tweezer assembly, a light spot forming assembly, a sample pool (11), and a position sensitive detector assembly; the sample pool (11) is used for placing a sample to be measured; the optical tweezer assembly is used for capturing the head of a target sperm in the sample to be measured in the sample pool (11); the light spot forming assembly is used for forming a light spot of the head of the target sperm captured by the optical tweezer assembly; the position sensitive detector assembly is used for receiving the light spot of the head of the target sperm formed by the light spot forming assembly, acquiring light spot intensity change information, converting the light spot intensity change information into electrical signal data, performing power spectrum analysis on the electrical signal data, and acquiring the rotation frequency of the head of the target sperm.

5. The device of claim 4, wherein the optical tweezer assembly comprises a first laser (1) and a lens for expanding the laser beam; the first laser (1) emits a first laser, which is transmitted through the first dichroic mirror (4) in the position sensitive detector assembly after being expanded by the lens, and then passes through the objective lens OBJ (5) to manipulate and position the head of the target sperm in the sample pool (11).

6. The device of claim 4, wherein the lens for expanding the laser beam comprises a first lens (2) and a second lens (3), and the first lens (2) and the second lens (3) are used to expand the laser beam emitted by the first laser (1). The light spot forming assembly comprises: a second laser (12), a second dichroic mirror (8), a first mirror (7), and a condenser lens CON (6); the second laser (12) emits a second laser, which is reflected by the second dichroic mirror (8) and the first mirror (7) and then condensed by the condenser lens CON (6) to the head region of the target sperm in the sample pool (11), thereby forming a light spot corresponding to the rotation of the head of the target sperm.

7. The apparatus of claim 4, wherein the apparatus further comprises a light source and a light detector. The light spot forming assembly further comprises: an LED light source (10) for providing illumination and a third lens (9). ​ 8. A device for measuring the frequency of rotation of the head of a sperm according to claim 7, characterized in that, ​ ​ The LED light source (10) emits illumination light, which is used to illuminate the sample cell (11) through the third lens (9), the second dichroic mirror (8), the first mirror (7) and the condenser CON (6) of the spot forming assembly.

9. The apparatus of claim 4, wherein the apparatus further comprises a light source and a light detector. The position sensitive detector assembly comprises: an objective lens OBJ (5), a first dichroic mirror (4), a third dichroic mirror (13), a fifth lens (16) for beam expansion, a position sensitive detector (17), a data acquisition card (18) and a computer (19); The position sensitive detector (17) receives the light beam reflected by the first dichroic mirror (4) and the third dichroic mirror (13) after passing through the objective lens OBJ (5) in the sample cell (11), and transmits the light spot intensity change information of the target sperm head after focusing by the fifth lens (16), converts the light spot intensity change information into electrical signal data and sends it to the data acquisition card (18), and the data acquisition card (18) sends the electrical signal data to the computer (19); The computer (19) receives the electrical signal data, performs power spectrum analysis on the electrical signal data, and obtains the rotation frequency of the target sperm head.

10. The apparatus of claim 4, wherein the apparatus further comprises a light source and a light detector. The device further comprises: an imaging acquisition assembly for acquiring image information of a sample to be tested in the sample cell (11), and selecting a target sperm based on the image information; The imaging acquisition assembly comprises a camera (15) and a fourth lens (14). After the light beam in the sample cell (11) is transmitted by the objective lens OBJ (5) in the position sensitive detector assembly, it is reflected by the first dichroic mirror (4), and then passes through the third dichroic mirror (13) and is transmitted to the camera (15) through the fourth lens (14), thereby generating image information in the sample cell (11).

Images