Optical detection system

Abstract

The present disclosure provides an optical detection system, comprising: a collimating module configured to generate collimated light; and at least one multi-channel detection module configured to receive the collimated light, wherein each of the at least one multi-channel detection module comprises: a first channel group comprising: a first filter array comprising a plurality of first filters arranged along a first axis; and a first detection component array comprising a plurality of first detection components arranged along a third axis and corresponding one-to-one to the plurality of first filters; and a second channel group comprising: a second filter array comprising a plurality of second filters arranged along a second axis; and a second detection component array comprising a plurality of second detection components arranged along a fourth axis and corresponding one-to-one to the plurality of second filters, wherein an absolute value of a first angle is the same as an absolute value of a second angle, the light propagates in an alternating manner between the first channel group and the second channel group, and the plurality of first filters and the plurality of second filters have different center wavelengths from each other.

Description

Technical Field

[0001] This disclosure relates to an optical detection system, and more particularly to an optical detection system for testing biological samples. Background Technology

[0002] Biological sample testing instruments, such as gene sequencers, are widely used in the medical and biological fields for the statistical analysis and classification of different cells. The optical system of a biological sample testing instrument typically includes a laser excitation system and a fluorescence collection and detection module system. In addition to collecting fluorescence, the fluorescence collection and detection module system also has the function of collecting side scattering. The fluorescence collection and detection module system typically includes a fluorescence objective lens and a fluorescence detection module.

[0003] In the optical system of a biosample analyzer, when multiple lasers of different wavelengths excite the same specific fluorescent dye, the resulting fluorescence spectra may overlap. Therefore, current biosample analyzers often employ a fluorescence collection module to spatially separate the fluorescence excited by different lasers before coupling it into multimode fiber end faces corresponding to different laser channels. The fiber connects to a pre-reserved fiber optic interface on the detection module. Through collimation by a fiber optic collimator, beam splitting by a beam splitter, and filtering by a bandpass filter, the fluorescence is ultimately separated into different wavelengths of fluorescence signals, which are received by a photodetector. Computer software then analyzes these different wavelength fluorescence signals one by one to determine the types and quantities of particles in the sample.

[0004] There are four main optical path structures for existing fluorescence detection modules. The first type uses a classic "tree-shaped" beam splitter. This type of fluorescence detection module mainly achieves beam splitting by using long-pass or short-pass filters for cutoff and band-pass filters for filtering. However, due to the steepness of the long-pass filter, for detection modules with a large number of channels and a channel bandwidth of less than 20nm, it inevitably causes a significant attenuation of channel fluorescence. In addition, the filters are expensive and bulky. The second type uses a "star-shaped optical path system" to collect and detect fluorescence signals. In this type of fluorescence detection module, a long focal length objective lens is used to collect fluorescence and limit divergence. However, aberrations and divergence angles during fluorescence transmission limit the number of fluorescence wavelengths that can be detected. At the same time, the fluorescence spot incident on the photosensitive surface of the detector is larger than 3mm. Therefore, this type of fluorescence detection module can only use a large surface area photomultiplier tube (PMT) as the detector, resulting in a large system size and high cost (due to the high price of PMTs). The third method uses a zigzag multiple reflection beam splitting to collect and detect fluorescence signals. Multiple micromirrors are arranged on one side, and multiple filters arranged in a row are placed on the opposite side. The incident light propagates back and forth in a zigzag pattern between the multiple consecutive filters and micromirrors, imaging the light onto the side where the filters are located. The light then enters the photodetector through focusing lenses in the channels of each filter. In this structure, the light energy reflection loss at the end of the channel is significant, and the optical path is long, requiring stringent optical path stability. Furthermore, in this type of structure, lateral divergence signals and fluorescence signals are often transmitted together, making the fluorescence channel susceptible to leakage from lateral divergence signals. The fourth method uses the Hreeiot multiple reflection principle to form a ring-shaped reflection ring. Filters with different bandwidths are placed at the position of the reflection ring to achieve fluorescence detection. This structure can be made smaller, but the light energy loss is comparable to the zigzag scheme, and it is sensitive to the fluorescence incident angle and the distance between the mirror and the filter, resulting in poor stability.

[0005] As the laser channels of existing biological sample testing instruments expand, the number of channels in the fluorescence detection module also needs to increase accordingly. However, the aforementioned optical path structures suffer from problems in practical applications, such as high light energy loss due to multiple reflections, large size, high cost, relatively complex optical path debugging, and poor channel scalability of the fluorescence lateral dispersion detection module. Therefore, it is necessary to propose a technical solution to address the problems existing in the above-mentioned technologies. Summary of the Invention

[0006] Therefore, the purpose of this disclosure is to provide an optical detection system, in particular its detection module, which has low light energy loss, low spectral / scattering leakage, short fluorescence transmission path, and simple optical path debugging.

[0007] The above objectives are achieved through the optical detection system described below.

[0008] This disclosure provides an optical detection system, comprising:

[0009] The collimation module is configured to generate collimated light; and

[0010] At least one multi-channel detection module is configured to receive the collimated light.

[0011] Each of the at least one multi-channel detection modules includes:

[0012] The first channel group includes:

[0013] A first filter array includes a plurality of first filters arranged along a first axis; and

[0014] The first detection component array includes a plurality of first detection components disposed along a third axis inclined at a first angle relative to the first axis and corresponding one-to-one with the plurality of first filters; and

[0015] The second channel group includes:

[0016] The second filter array includes a plurality of second filters arranged along a second axis parallel to the first axis; and

[0017] The second detection component array includes multiple second detection components arranged along a fourth axis tilted at a second angle relative to the second axis and corresponding one-to-one with the plurality of second filters, and...

[0018] Wherein, the absolute values ​​of the first angle and the second angle are the same, light propagates alternately between the first channel group and the second channel group, and the plurality of first filters and the plurality of second filters have different center wavelengths.

[0019] The optical detection system according to this disclosure may also have one or more of the following features, either individually or in combination.

[0020] In one embodiment, the optical detection system includes at least one fluorescence spectrometer and at least two multi-channel detection modules.

[0021] In one embodiment, the first filter array includes at least four first filters, and the second filter array includes at least four second filters.

[0022] In one embodiment, the first channel group includes a first concave mirror disposed between the plurality of first filters and configured to converge light onto a second filter located directly downstream of the first concave mirror in the optical path; the second channel group includes a second concave mirror disposed between the plurality of second filters and configured to converge light onto a first filter located directly downstream of the second concave mirror in the optical path.

[0023] In one embodiment, the first concave mirror is disposed along the first axis between the nth and (n+1)th of the plurality of first filters, and the second concave mirror is disposed along the second axis between the nth and (n+1)th from the end of the plurality of second filters.

[0024] In one embodiment, each of the at least one multi-channel detection module has an optical transmission rate of at least 80%.

[0025] In one embodiment, the first concave mirror and / or the second concave mirror are adjustable.

[0026] In one embodiment, each of the at least one multi-channel detection module further includes a plane mirror configured to reflect the collimated light to the first channel group.

[0027] In one embodiment, the detection surfaces of the plurality of first detectors included in the first detection component array are on a single plane or on a plurality of planes that are parallel to each other and offset from each other, and the detection surfaces of the plurality of second detectors included in the second detection component array are on a single plane or on a plurality of planes that are parallel to each other and offset from each other.

[0028] In one embodiment, the optical detection system includes at least three fluorescence spectrometers and at least four multi-channel detection modules.

[0029] In one embodiment, the first filter array includes at least two first filters, and the second filter array includes at least two second filters.

[0030] In one embodiment, each of the at least one multi-channel detection modules further includes an entrance reflector, which is a planar reflector or a concave reflector, and is configured to reflect light to a corresponding first channel group.

[0031] In one embodiment, the optical detection system further includes: a lateral beam splitter configured to receive the collimated light and separate the lateral beam from the fluorescent light; and a lateral detection module configured to receive the lateral beam, wherein the at least one multi-channel detection module is configured to receive the fluorescent light.

[0032] In one embodiment, the absolute value of the maximum incident angle of each of the plurality of first filters and the plurality of second filters is equal to the absolute value of the first angle.

[0033] In one embodiment, the signal-to-noise ratio of each of the at least one multi-channel detection modules is greater than 43 dB. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings of the embodiments of this disclosure will be briefly described below. The drawings are merely illustrative of some embodiments of this disclosure and are not intended to limit the scope of all embodiments of this disclosure. In the drawings:

[0035] Figure 1a A schematic diagram of an optical detection system according to an embodiment of the present disclosure is shown.

[0036] Figure 1b A schematic diagram of an optical detection system according to another embodiment of this disclosure is shown.

[0037] Figure 2 A schematic diagram of an optical inspection system according to yet another embodiment of the present disclosure is shown.

[0038] Figure 3 A schematic diagram of a conventional "zigzag glass block transmission" type optical inspection system with 16 channels is shown.

[0039] Figure 4 A schematic diagram of a conventional "zigzag air transmission" type optical detection system with 16 channels is shown. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0041] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the terms “an” or “a” and similar terms do not necessarily indicate a quantity limitation. The terms “comprising,” “including,” or “having,” and similar terms mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. The terms “connected” or “connected,” and similar terms are not limited to the physical or mechanical connection or connection shown in the drawings, but may include equivalent connections or connections, whether direct or indirect. The terms “upper,” “lower,” “left,” and “right,” etc., are used only to indicate relative positional relationships, which may change accordingly when the absolute position of the described object changes.

[0042] The following is for reference. Figures 1a to 2 The various embodiments of the optical inspection system according to the present disclosure are described in detail. Figure 1a An optical inspection system comprising two multi-channel detection modules is shown, each having eight channels. Similarly, Figure 1b An optical inspection system comprising two multi-channel inspection modules is also shown, each having eight channels. Figure 1a and Figure 1b The difference is that, Figure 1a The distances along the light propagation direction between the filter array and the corresponding detection component array are equal, while Figure 1b The distances along the light propagation direction between the filter array and the corresponding detection component array are different. Figure 2 An optical inspection system comprising four multi-channel detection modules is shown, each having four channels. It should be noted that this disclosure is not limited to what is shown in the figures; systems with more or fewer multi-channel detection modules and more or fewer channels are possible depending on the application. Furthermore, an odd number of multi-channel detection modules and an odd number of channels are also possible.

[0043] like Figure 1a and Figure 1b As shown, an optical detection system according to one embodiment of the present disclosure may include an optical fiber 100, a collimation module 200, and at least one multi-channel detection module 10, 20. Furthermore, in some examples, the optical detection system may also include a fluorescence beam splitter 300. Further, in some examples, the optical detection system may also include a lateral beam splitter 30 and a lateral detection module 40.

[0044] Fiber 100, also known as the input fiber, is used to receive and transmit light from the object being tested, including fluorescent light and lateral astigmatism. Fluorescent light is generated when the object being tested is irradiated with excitation light; it has a different wavelength than the excitation light and can reflect the chemical properties of the object. Lateral astigmatism is scattered light generated when the object being tested is irradiated with excitation light at a non-direct angle; it has the same wavelength as the excitation light. The excitation light can be, for example, light produced by a laser, with a wavelength of, for example, 405 nm.

[0045] For example, the core diameter of fiber 100 is between 200 and 800 μm, such as 400 μm or 600 μm, and the numerical aperture (NA) is between 0.1 and 0.4, such as 0.12 or 0.2. Of course, other values ​​are also possible.

[0046] The collimation module 200 is positioned directly downstream of the optical fiber 100 in the optical path, receiving light from the optical fiber 100 and generating collimated light based on the received light. Furthermore, the collimation module 200 transmits the collimated light to subsequent optical elements or optical assemblies. For example, the collimation module 200 may include an achromatic cemented second lens, an achromatic cemented third lens, or an air-spaced achromatic lens, thereby eliminating chromatic aberration during multi-wavelength light transmission.

[0047] The side-split beam splitter 30 is positioned directly downstream of the collimation module 200 in the optical path to receive the collimated light and separate the side-split light from the fluorescent light in the collimated light. For example, the side-split beam splitter 30 can be a filter that reflects the cutoff light (including the side-split light) and transmits the fluorescent light. Alternatively, the side-split beam splitter 30 can transmit the side-split light and reflect the fluorescent light.

[0048] It should be noted that "A is directly downstream of B" as described in this disclosure means that there are no other optical elements between A and B.

[0049] A fluorescence spectrometer 300 is positioned in the transmission optical path downstream of the side-scattering spectrometer 30. It receives the fluorescence light and splits it into two parts according to wavelength for transmission. For example, the fluorescence spectrometer 300 is a filter that transmits the first part of the fluorescence light to the multi-channel detection module 10 and reflects the second part of the fluorescence light to the multi-channel detection module 20.

[0050] The lateral dispersion detection module 40 is positioned in the reflected optical path downstream of the lateral dispersion beam splitter 30 to receive the lateral dispersion light, and may include a narrowband filter 41, a focusing lens 42, and a photodetector 43. The narrowband filter 41 further filters the cutoff light from the lateral dispersion beam splitter 30, and the focusing lens 42 focuses the lateral dispersion light onto the photodetector 43.

[0051] Multichannel detection modules 10 and 20 are configured to receive fluorescence light for fluorescence-based detection. Each of the multichannel detection modules 10 and 20 includes a plurality of detection channels divided according to wavelength. In some embodiments, the optical detection system may include only one multichannel detection module 10, which may, for example, directly receive collimated light from the collimation module 200. Multichannel detection modules 10 and 20 may be mounted in their respective housings or on brackets.

[0052] Lateral astigmatism signals are stronger than fluorescence signals, thus causing noise in the fluorescence channel detection. As mentioned above, this disclosure separates the lateral astigmatism detection module from the multi-channel detection module, thereby effectively reducing the impact of lateral astigmatism on fluorescence channel leakage and decreasing fluorescence channel noise. Simulation calculations show that embodiments of this disclosure can reduce lateral astigmatism signal leakage to the fluorescence channel by more than 10 times, as detailed below.

[0053] See you again Figure 1a and Figure 1b The multi-channel detection modules 10 and 20 have similar or even identical structures. Here, we will take the multi-channel detection module 10 as an example for explanation. The description of the multi-channel detection module 10 in this article also applies to the multi-channel detection module 20.

[0054] The multi-channel detection module 10 includes a first channel group and a second channel group, wherein the first channel group is located on the left side of the figure and the second channel group is located on the right side of the figure. The two channel groups are arranged approximately in parallel.

[0055] The first channel group may include a first filter array and a first detection component array. The second channel group may include a second filter array and a second detection component array.

[0056] The first filter array includes a plurality of first filters 101, 105, 107, and 109 arranged along the first axis A1. Figure 1a The first detection component array includes multiple first detection components arranged along at least one third axis A3, A3', A3'', A3''' inclined at a first angle α1 relative to the first axis A1 and corresponding one-to-one with multiple first filters 101, 105, 107, 109. Figure 1b The first detection component array comprises multiple first detection components arranged along a third axis A3''' tilted at a first angle α1 relative to the first axis A1. Each first detection component includes a focusing lens and a first detector (hereinafter also referred to as a photodetector).

[0057] The second filter array includes a plurality of second filters 102, 104, 106, and 110 arranged along a second axis A2 parallel to the first axis A1. Figure 1aThe second detection component array includes multiple second detection components arranged along at least one fourth axis A4, A4', A4'', A4''' inclined at a second angle α2 relative to the second axis A2 and corresponding one-to-one with multiple second filters 102, 104, 106, 110. Figure 1b The second detection array comprises multiple second detection components arranged along a fourth axis A4''' tilted at a second angle α2 relative to the second axis A2. Each second detection component includes a focusing lens and a second detector (hereinafter also referred to as a photodetector).

[0058] The absolute values ​​of the first angle α1 and the second angle α2 can be the same, but they can have different signs. For example, the third axis A3 is obtained by rotating the first axis A1 clockwise by the first angle α1, and the fourth axis A4 is obtained by rotating the second axis A2 counterclockwise by the second angle α2. Figure 1a The four third axes A3, A3', A3'', and A3''' shown are parallel to each other. Figure 1a The four fourth axes A4, A4', A4'', and A4''' shown are parallel to each other.

[0059] Light propagates alternately between the first and second channel groups, and the multiple first filters and multiple second filters have different center wavelengths. Compared with conventional solutions, the optical detection system disclosed herein does not require multiple consecutively arranged concave mirrors, has a shorter optical path, thus resulting in less light energy loss, and significantly reduces the difficulty of optical path adjustment, making it easy to implement with the help of fixtures.

[0060] like Figure 1a and Figure 1b As shown, the first filter array may include four first filters 101, 105, 107, and 109, and the second filter array may include four second filters 102, 104, 106, and 110.

[0061] With both the first and second channel groups having four filters, the multi-channel detection module 10 achieves eight-channel detection. For example... Figure 1a and Figure 1bAs shown, the first channel includes a filter 101, a focusing lens 111, and a photodetector 119; the second channel includes a filter 102, a focusing lens 112, and a photodetector 120; the third channel includes a filter 104, a focusing lens 113, and a photodetector 121; the fourth channel includes a filter 105, a focusing lens 114, and a photodetector 122; the fifth channel includes a filter 106, a focusing lens 115, and a photodetector 123; the sixth channel includes a filter 107, a focusing lens 116, and a photodetector 124; the seventh channel includes a filter 109, a focusing lens 117, and a photodetector 125; and the eighth channel includes a filter 110, a focusing lens 118, and a photodetector 126.

[0062] In some examples not shown, such as in Figure 1a or Figure 1b In the variant, the intensity of the fluorescent light is high enough that the first filter array can include more first filters, and the second filter array can also include more second filters.

[0063] Furthermore, the first channel group includes a first concave mirror 103 disposed between a plurality of first filters and configured to converge light onto a second filter located directly downstream of the first concave mirror 103 in the optical path. The second channel group includes a second concave mirror 108 disposed between a plurality of second filters and configured to converge light onto a first filter located directly downstream of the second concave mirror 108 in the optical path.

[0064] For example, a first concave mirror 103 is disposed along a first axis A1 between the nth and (n+1th)th filters in a plurality of first filters, and a second concave mirror 108 is disposed along a second axis A2 between the nth and (n+1th)th filters from the end in a plurality of second filters. Figure 1a As shown, a first concave mirror 103 is disposed along a first axis A1 between the first first filter 101 and the second first filter 105 among a plurality of first filters, and a second concave mirror 108 is disposed along a second axis between the penultimate second filter 110 and the penultimate second filter 106 among a plurality of second filters. Alternatively, the first concave mirror 103 is disposed along the first axis A1 between the first channel and the fourth channel, and the second concave mirror 108 is disposed along the second axis A2 between the fifth channel and the eighth channel. Alternatively, along the direction of light propagation, the first concave mirror 103 is disposed between the second channel and the third channel, and the second concave mirror 108 is disposed between the sixth channel and the seventh channel.

[0065] For example, the surfaces of the first concave mirror 103 and the second concave mirror 108 may be coated with a high-reflectivity dielectric film, which has a high reflectivity (e.g., >99.5%) for light entering the multi-channel detection module 10.

[0066] The first concave mirror 103 and / or the second concave mirror 108 are adjustable. For example, the position and / or orientation of the first concave mirror 103 and / or the second concave mirror 108 are adjustable. In this way, offsets in light propagation can be compensated for, making the system more compact.

[0067] By placing a concave mirror at an appropriate position along the propagation path of fluorescent light, the spot size of the fluorescent light can be reduced, preventing the spot from growing larger as the light propagates and exceeding the aperture of the filter. In other words, the concave mirror has a suppressive effect on fluorescent light divergence.

[0068] like Figure 1a As shown, the first detectors 119, 122, 124, and 125 of the first detection array in the first channel group are arranged along the third axis A3, A3', A3'', and A3''', respectively, and the second detectors 120, 121, 123, and 126 of the second detector array in the second channel group are arranged along the fourth axis A4, A4', A4'', and A4''', respectively. Alternatively, it can be said that the detection surfaces of the first detectors or photodetectors of the multiple first detection components in the first detection array are on multiple planes that are parallel and staggered from each other, and the detection surfaces of the second detectors or photodetectors of the multiple second detection components in the second detection array are on multiple planes that are parallel and staggered from each other.

[0069] In such Figure 1b In other examples shown, the first detectors 119, 122, 124, and 125 of the first detection component array of the first channel group are arranged along the same third axis A3''', and the second detectors 120, 121, 123, and 126 of the second detection component array of the second channel group are arranged along the same fourth axis A4'''. Figure 1b In the example shown, the distance between the first filter of the first channel group and the corresponding first detection component (or corresponding focusing lens) varies in different channels, and the second channel group has the same situation. The filters and corresponding focusing lenses in the channel group form an approximately V-shaped distribution. This ensures that the detection surfaces of the multiple first detectors included in the first detection component array are on the same plane, and the detection surfaces of the multiple second detectors included in the second detection component array are on the same plane. Therefore, it is not necessary to bend the detector pins during detector installation, resulting in better manufacturability and facilitating the assembly and adjustment of the detectors and the system.

[0070] Based on the above description of the first and second concave mirrors, it can be seen that the first concave mirror 103 and the second concave mirror 108 are respectively disposed in the channel groups on both sides. Their positions are chirally symmetrical, that is, the positions of the two concave mirrors are the same in both the forward and reverse order arrangement of the channels on both sides. Therefore, the external mechanical structures and hardware circuit boards of the channel groups on both sides can be reused. Figure 1bAs shown, the first detection component array of the first channel group can be moved to serve as the second detection component array of the second channel group, and the second detection component array of the second channel group can also be moved to serve as the first detection component array of the first channel group.

[0071] The multi-channel detection module 10 further includes a plane mirror 130 configured to reflect fluorescent light (or possibly collimated light from the collimation module 200) to the first channel group. For example, the surface of the plane mirror 130 is coated with a dielectric reflective film, exhibiting high reflectivity (e.g., >99.5%) for light entering the multi-channel detection module. By using a plane mirror near the light inlet of the multi-channel detection module, optical path folding can be achieved, ensuring the multi-channel detection module has more channels while making the system more compact.

[0072] like Figure 1a and Figure 1b As shown, to achieve more channels, the light incident on the first filter has a non-zero angle of incidence. To ensure that the light transmitted through the first filter propagates through the center of the corresponding focusing lens and is focused onto the corresponding photodetector, the focusing lens and photodetector corresponding to the first filter should be tilted at an angle relative to the first filter. For example, the absolute value of the maximum angle of incidence of the first filter is equal to the absolute value of the first angle α1. That is, the angle at which the focusing lens and photodetector corresponding to the first filter are tilted relative to the first filter is the same as the absolute value of the maximum angle of incidence of the first filter. The same applies to the second filter, i.e., the absolute value of the maximum angle of incidence of the second filter is equal to the absolute value of the second angle α2.

[0073] For example, the first and second filters can be bandpass filters with different bandwidths, and their incident angles and incident cone angles differ from those of conventional filters. For instance, the CHA of the first and second filters is greater than 3°, and their incident angles are less than or equal to 15°. That is, the maximum incident angle of the first and second filters can be 15°, and the absolute values ​​of the first angle α1 and the second angle α2 mentioned above can be 15°.

[0074] For example, the focusing lenses for channels one through eight described above have the same parameters. For instance, they can be plano-convex lenses or aspherical lenses.

[0075] For example, the photodetectors of the first to eighth channels mentioned above can be APD (Avalanche Photodiode) or SIPM (Silicon Photomultiplier).

[0076] Figure 1a and Figure 1bThe multi-channel detection module 20 shown has a substantially the same structure as the multi-channel detection module 10, except that the optical elements therein are indicated by a reference numeral 100 higher than those in the multi-channel detection module 10. Their functions and roles are not described further here. Similarly, the multi-channel detection module 20 also includes a plane mirror 230, a first channel group located on the right side of the figure, and a second channel group located on the left side of the figure. The first channel group of the multi-channel detection module 20 also includes a first concave mirror 203, and the second channel group also includes a second concave mirror 208.

[0077] The filters in the multi-channel detection modules 10 and 20 have different center wavelengths from each other, therefore Figure 1a and Figure 1b The optical inspection systems shown can each have a total of 16 inspection channels.

[0078] The multi-channel detection modules 10 and 20 disclosed herein each have an optical transmittance of at least 80%. Specifically, the optical energy loss of each detection channel of the multi-channel detection modules 10 and 20 is less than 20%.

[0079] Table 1 below shows the relationship between this disclosure and Figure 3 and 4 A comparison of light energy loss in the conventional scheme is shown. (Regarding...) Figure 1a and Figure 1b For example, in Table 1, τ1-τ8 represent the optical transmission rates of the first to eighth channels in the multi-channel detection module 10, and τ9-τ16 represent the optical transmission rates of the first to eighth channels in the multi-channel detection module 20. (For...) Figure 3 and 4 In Table 1, τ1-τ16 represent the optical transmission rates of the first to sixteenth channels, as indicated by the numbers 1, 2, 3...16 in the figure.

[0080] against Figure 1a and Figure 1b For example, assuming the total luminous flux of the incident fluorescence is Ф, the transmittance of the side-scattering beam splitter 30 is 98%, the reflectance is 98%, the average transmittance of the center wavelength of each filter (such as the bandpass filter) is 93%, the cutoff band reflectance of each filter is 99.999%, the reflectance of the plane mirrors 130 and 230 is 97.5%, the reflectance of the concave mirrors 103, 108, 203 and 208 is 97%, and the transmittance of the focusing lens is 99.5%, then the light transmission rate (also called transmittance) τ of the incident fluorescence reaching the detectors of the 16 channels is calculated as shown in Table 2.

[0081] against Figure 3For example, assuming the total incident fluorescence flux in the zigzag scheme is Ф, the glass block transmittance is 99%, the average transmittance of the bandpass filter at the center wavelength is 93%, the bandpass filter cutoff band reflectance is 99.999%, and the concave mirror (i.e., Figure 3 The reflectivity of the optical element on the right side of the glass block is 97%, and the transmittance of the focusing lens is 99.5%. The light transmission rate τ of the incident fluorescence reaching the detectors of the 16 channels is calculated as shown in Table 3.

[0082] against Figure 4 For example, assuming the total incident fluorescence flux in the "zigzag" scheme is Ф, the average transmittance of the bandpass filter at the center wavelength is 93%, the reflectance of the bandpass filter at the cutoff band is 99.999%, and the concave mirror (i.e., Figure 4 The reflectivity of the optical element on the right side of the image is 97%, and the transmittance of the focusing lens is 99.5%. The transmittance τ of the incident fluorescence reaching the 16-channel detector is calculated as shown in Table 4.

[0083] Table 1

[0084]

[0085] Table 2

[0086]

[0087] Table 3

[0088]

[0089] Table 4

[0090]

[0091] As shown in Table 1, the light energy loss of all channels in this disclosure is below 20%, while the light energy loss of the end channels in conventional "zigzag glass block transmission" and "zigzag air transmission" schemes is above 40%. Therefore, in terms of light energy loss, the optical detection system of this disclosure is more advantageous.

[0092] Through the design of separating the lateral dispersion detection module and the multi-channel detection module as described above, each channel of the multi-channel detection modules 10 and 20 disclosed herein has a low noise value. For example, the signal-to-noise ratio of each channel of the multi-channel detection modules 10 and 20 is greater than 43 dB.

[0093] Assuming the lateral dispersion detection module and the multi-channel detection module are not separated, Figure 1a and Figure 1bThe first channel in the multi-channel detection module 10 shown (as the red light detection module of the biosample testing instrument) is replaced with a lateral dispersion detection channel, and the rest of the settings are the same. Assuming that 3-micron polystyrene microspheres (Thermo Fisher 4K-03 microspheres) are tested on the biosample testing system, the results shown in Table 5 can be obtained.

[0094] Table 5

[0095]

[0096] As shown in Table 5, the noise floor caused by scattered light leakage in the scheme where the lateral dispersion detection module and the multi-channel detection module are not separated is at least 10 times that of the separated scheme. Therefore, the embodiments of this disclosure effectively reduce the noise floor caused by scattered light leakage in the detection module.

[0097] like Figure 2 As shown, an optical detection system according to another embodiment of this disclosure includes three fluorescence spectrometers 300, 400, and 500 and four multi-channel detection modules 600, 700, 800, and 900. Of course, in Figure 2 It is also possible to add more fluorescence spectrometers and more multi-channel detection modules on top of the existing structure. For example, three fluorescence spectrometers 300, 400, and 500 can be in the form of filters. Collimated light from collimation module 200 is incident on fluorescence spectrometer 300, the reflected light is incident on multi-channel detection module 600, and the transmitted light is incident on fluorescence spectrometer 400; the transmitted light from fluorescence spectrometer 400 is incident on multi-channel detection module 700, and the reflected light is incident on fluorescence spectrometer 500; the transmitted light from fluorescence spectrometer 500 is incident on multi-channel detection module 800, and the reflected light is incident on multi-channel detection module 900.

[0098] and Figure 1a and 1bSimilarly, multi-channel detection modules 600, 700, 800, and 900 each have a first channel group and a second channel group. The first filter array of the first channel group of multi-channel detection module 600 includes two first filters 602 and 604 arranged along a first axis A1, and the second filter array of the second channel group includes two second filters 603 and 605 arranged along a second axis A2 parallel to the first axis A1. It is also possible for the first filter array to include a greater number of first filters, and for the second filter array to include a greater number of second filters. The first detection component array of the first channel group of multi-channel detection module 600 includes a plurality of first detection components arranged along at least one third axis A3 and A3' inclined at a first angle α1 relative to the first axis A1 and corresponding one-to-one with the two first filters 602 and 604. Each first detection component includes a focusing lens and a photodetector. The second detection component array of the second channel group of the multi-channel detection module 600 includes multiple second detection components arranged along at least one fourth axis A4, A4' inclined at a second angle α2 relative to the second axis A2 and corresponding one-to-one with the two second filters 603, 605. Each second detection component includes a focusing lens and a photodetector. The absolute values ​​of the first angle α1 and the second angle α2 can be the same, but they can have different signs. Figure 2 The two third axes A3 and A3' shown are parallel to each other, and the two fourth axes A4 and A4' are also parallel to each other. Light propagates alternately between the first and second channel groups, and the multiple first filters and multiple second filters have different center wavelengths. Figure 2 As shown, the multi-channel detection module 600 implements four detection channels. The first channel includes a filter 602, a focusing lens 606, and a photodetector 610; the second channel includes a filter 603, a focusing lens 607, and a photodetector 611; the third channel includes a filter 604, a focusing lens 608, and a photodetector 612; and the fourth channel includes a filter 605, a focusing lens 609, and a photodetector 613.

[0099] Similarly, multi-channel detection modules 700, 800, and 900 also implement four detection channels respectively. It should be noted that the description of multi-channel detection module 600 is applicable to multi-channel detection modules 700, 800, and 900 accordingly. The first channel of multi-channel detection module 700 includes a filter 702, a focusing lens 706, and a photodetector 710; the second channel includes a filter 703, a focusing lens 707, and a photodetector 711; the third channel includes a filter 704, a focusing lens 708, and a photodetector 712; and the fourth channel includes a filter 705, a focusing lens 709, and a photodetector 713. The multi-channel detection module 800 has the following characteristics: First channel includes a filter 802, a focusing lens 806, and a photodetector 810; second channel includes a filter 803, a focusing lens 807, and a photodetector 811; third channel includes a filter 804, a focusing lens 808, and a photodetector 812; fourth channel includes a filter 805, a focusing lens 809, and a photodetector 813. The multi-channel detection module 900 has the following characteristics: First channel includes a filter 902, a focusing lens 906, and a photodetector 910; second channel includes a filter 903, a focusing lens 907, and a photodetector 911; third channel includes a filter 904, a focusing lens 908, and a photodetector 912; fourth channel includes a filter 905, a focusing lens 909, and a photodetector 913.

[0100] like Figure 2 As shown, each of the multi-channel detection modules 600, 700, 800, and 900 further includes an entrance reflector, which is either a plane reflector or a concave reflector, and is configured to reflect light to the corresponding first channel group. For example, the entrance reflector 601 of the multi-channel detection module 600 can be either a plane reflector or a concave reflector. For example, the entrance reflectors 701, 801, and 901 of each of the multi-channel detection modules 700, 800, and 900 can each be concave reflectors, and can have different converging capabilities.

[0101] Because the number of channels in each multichannel detection module is reduced, the additional concave mirrors used to converge fluorescence light in the channel group can be omitted.

[0102] Figure 2 In the illustrated embodiment, the filters are continuously distributed, resulting in a shorter optical path and less light energy loss in the multi-channel detection module.

[0103] exist Figure 2 In a variation of the embodiment shown, the multi-channel detection module 600 can be replaced with the lateral dispersion detection module as described above, or a lateral dispersion splitter can be set between the collimation module 200 and the fluorescence spectrometer 300, and an additional lateral dispersion detection module can be provided.

[0104] Similar to Figure 1a and 1b , Figure 2 The embodiments can also achieve that each channel of the multi-channel detection module has an optical transmission rate of at least 80%, and the signal-to-noise ratio of each channel of the multi-channel detection module is greater than 43 dB.

[0105] As described above, the optical detection system of this disclosure guides fluorescence light to different multi-channel detection modules based on long and short wavelengths, effectively reducing the optical path transmission path of the end channel by transmitting and detecting them separately. Each multi-channel detection module of this disclosure adopts a layout with fluorescence detection channels arranged on both sides, further reducing the optical path transmission path of the end channel, reducing the number of reflections, and lowering reflection loss. This disclosure adopts a separate design for the lateral dispersion detection module and the multi-channel detection module, effectively reducing the background noise caused by leakage of background scattered light in the detection channel. Each channel group of the multi-channel detection module of this disclosure, distributed on both sides, has at least one concave reflector, achieving dispersion suppression of fluorescence light and facilitating further expansion of the number of detection module channels. The concave reflectors of this disclosure are chiral symmetrical in the corresponding multi-channel detection modules, thus enabling the reuse of external mechanical structures and hardware circuit boards for the multi-channel detection modules, and making module assembly and adjustment simpler and easier.

[0106] The technical features disclosed above are not limited to the combinations of the disclosed features with other features. Those skilled in the art can also make other combinations of the technical features according to the purpose of the invention to achieve the purpose of this disclosure.

Claims

1. An optical inspection system, comprising: Collimation module (200), configured to generate collimated light; as well as At least one multi-channel detection module (10, 20); (600, 700, 800, 900), configured to receive the collimated light, Each of the at least one multi-channel detection modules includes: The first channel group includes: The first filter array includes a plurality of first filters arranged along a first axis (A1); and A first detection component array includes a plurality of first detection components arranged along a third axis (A3, A3', A3'', A3''') tilted at a first angle (α1) relative to a first axis (A1) and corresponding one-to-one with the plurality of first filters; and The second channel group includes: The second filter array includes a plurality of second filters arranged along a second axis (A2) parallel to the first axis (A1); and The second detection component array includes multiple second detection components arranged along a fourth axis (A4, A4', A4'', A4''') at a second angle (α2) tilted relative to the second axis and corresponding one-to-one with the plurality of second filters, and... Wherein, the absolute values ​​of the first angle (α1) and the second angle (α2) are the same, light propagates alternately between the first channel group and the second channel group, and the plurality of first filters and the plurality of second filters have different center wavelengths from each other; The first filter array includes at least four first filters (101, 105, 107, 109), and the second filter array includes at least four second filters (102, 104, 106, 110). The first channel group includes a first concave mirror (103) disposed between the plurality of first filters and configured to focus light onto a second filter located directly downstream of the first concave mirror in the optical path; The second channel group includes a second concave mirror (108) disposed between the plurality of second filters and configured to converge light onto a first filter located directly downstream of the second concave mirror in the optical path; and The first concave mirror is disposed along the first axis (A1) between the nth and (n+1)th of the plurality of first filters, and the second concave mirror is disposed along the second axis (A2) between the nth and (n+1)th from the end of the plurality of second filters.

2. The optical detection system according to claim 1, wherein, The optical detection system includes at least one fluorescence spectrometer (300) and at least two multi-channel detection modules (10, 20).

3. The optical detection system according to claim 2, wherein, The first concave mirror (103) and / or the second concave mirror (108) are adjustable.

4. The optical detection system according to claim 2, wherein, Each of the at least one multi-channel detection modules further includes a plane mirror (130; 230) configured to reflect the collimated light to the first channel group.

5. The optical detection system according to claim 1, wherein, The detection surfaces of the multiple first detectors in the first detection component array are on a single plane or on multiple planes that are parallel to each other and staggered. The detection surfaces of the multiple second detectors in the second detection component array are on a single plane or on multiple planes that are parallel to each other and staggered.

6. The optical detection system according to claim 1, wherein, The optical detection system includes at least three fluorescence spectrometers (300, 400, 500) and at least four multi-channel detection modules (600, 700, 800, 900).

7. The optical detection system according to claim 6, wherein, The first filter array includes at least two first filters (602, 604; 702, 704; 802, 804; 902, 904), and the second filter array includes at least two second filters (603, 605; 703, 705; 803, 805; 903, 905).

8. The optical detection system according to claim 7, wherein, Each of the at least one multi-channel detection modules further includes an entrance reflector (601; 701; 801; 901), which is a plane reflector or a concave reflector and is configured to reflect light to the corresponding first channel group.

9. The optical inspection system according to any one of claims 1 to 8, wherein, The optical detection system also includes: A side-scattering beam splitter (30) is configured to receive the collimated light and separate the side-scattered light from the fluorescent light; and The lateral dispersion detection module (40) is configured to receive the lateral dispersion light. The at least one multi-channel detection module is configured to receive the fluorescent light.

10. The optical inspection system according to any one of claims 1 to 8, wherein, The absolute value of the maximum incident angle of each of the plurality of first filters and the plurality of second filters is equal to the absolute value of the first angle.

11. The optical inspection system according to any one of claims 1 to 8, wherein, Each of the at least one multi-channel detection module has an optical transmission rate of at least 80%.

12. The optical inspection system according to any one of claims 1 to 8, wherein, The signal-to-noise ratio of each of the at least one multi-channel detection modules is greater than 43 dB.

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