Dichroic prism and fluorescence detection system with the same

Abstract

This invention relates to a two-dimensional beam splitter prism and a fluorescence detection system incorporating the prism. The two-dimensional beam splitter prism comprises a pentagonal prism and a wedge with the same refractive index. An excitation light filter layer is deposited on the first right-angle face of the pentagonal prism, an excitation light reflection layer is deposited on the first inclined face, and a two-dimensional dichroic film layer is deposited on the third inclined face. A single-layer SiO2 thin film is deposited on the fourth inclined face of the wedge, which is then bonded to the third inclined face with the dichroic film layer. An emission light filter layer is deposited on the third right-angle face, which is parallel to the second right-angle face. This invention's two-dimensional beam splitter prism simultaneously deposits the laser filter, emission filter, and dichroic film onto a single pentagonal prism assembly, facilitating instrument assembly and improving instrument accuracy. Furthermore, the two-dimensional beam splitter prism has an incident angle of 22.5 degrees, a steep transition band between the excitation and emission wavelengths, and minimal polarization separation, effectively separating the excitation light and fluorescence.

Description

Technical Field

[0001] This invention relates to the field of fluorescence detection, and more particularly to a bidirectional beam splitter and a fluorescence detection system incorporating the bidirectional beam splitter. Background Technology

[0002] A fluorescence detector is a computer-controlled chemical analysis instrument that analyzes fluorescent substances under an excitation light source, analyzing the proportion and composition of the fluorescent substances. Fluorescence analyzers are generally suitable for applications and research in chemistry and medicine. Laser-induced fluorescence detection technology has become a widely used detection method due to its high sensitivity with a single wavelength laser and ease of implementation on a chip. The optical system of a conventional fluorescence detector uses an excitation laser to emit a laser beam that passes through a dichroic mirror to illuminate the sample, generating fluorescence that enters the detection instrument through the dichroic mirror.

[0003] like Figure 8 As shown, the existing fluorescence detection system's prism assembly consists of a separately configured excitation filter 5, a dichroic mirror 7, and an emission filter 6. This is inconvenient to install, and the incident angle is 45°. When large-angle light is incident obliquely on the optical film of the dichroic beam splitter, the tangential components of the electric and magnetic fields in each film layer must remain continuous, resulting in a difference in the effective refractive index of the P-component and S-component of the light, which leads to the generation of polarization effect. The fabricated dichroic beam splitter has a low steepness in the band transition region and a large polarization separation in its spectral characteristics. In particular, if the angle is slightly off during assembly, it will not be able to meet the effective separation of the emission spectrum and the receiving spectrum detection channels.

[0004] In view of the shortcomings of the existing technology, it is urgent to provide a fluorescence detection system with high steepness and small polarization effect when incident at low angle. Summary of the Invention

[0005] This invention provides a dichroic beam splitter and a fluorescence detection system incorporating the dichroic beam splitter. The dichroic beam splitter of this invention simultaneously deposits a laser filter, an emission filter, and a dichroic separation film onto a single pentagonal prism assembly, facilitating instrument assembly and improving instrument accuracy. Furthermore, the dichroic beam splitter has an incident angle of 22.5 degrees, a steep transition band between the excitation and emission wavelengths, and minimal polarization separation, effectively separating the excitation light and fluorescence.

[0006] The technical solution of the present invention is as follows:

[0007] A two-dimensional beam splitter consists of a pentagonal prism and a wedge plate, both having the same refractive index.

[0008] The five prism faces of the pentagonal prism are composed of right-angle face one, right-angle face two, inclined face one, inclined face two, and inclined face three. Right-angle face one is the incident right-angle face and is perpendicular to right-angle face two. One side edge of inclined face one is connected to right-angle face two and the included angle between them is 112.5°. One side edge of inclined face three is connected to right-angle face one and the included angle between them is 112.5°. The two sides of inclined face two are connected to the other sides of inclined face one and inclined face three respectively, and the included angle between adjacent inclined faces is 112.5°.

[0009] The wedge-shaped plate is composed of a fourth inclined plane, a third right-angled plane forming a 22.5° angle with the fourth inclined plane, and a fourth right-angled plane forming a 67.5° angle with the fourth inclined plane.

[0010] An excitation light filter film is deposited on the right-angled surface one, an excitation light reflection film is deposited on the inclined surface one, and a dichroic film is deposited on the inclined surface three.

[0011] After a single layer of SiO2 thin film is deposited on the inclined surface four of the wedge plate, it is bonded to the inclined surface three, which is deposited with a dihedral color separation film. An emission filter film is deposited on the right-angled surface three, and the right-angled surface three is parallel to the right-angled surface two.

[0012] Specifically, the spectral parameters of the excitation light filter film are: Tavg < 0.1% @ 300-565 & 595-1000 nm, Tavg > 95% @ 575-585 nm, and AOI = 0°;

[0013] The spectral properties of the light-emitting filter film are: Tavg < 0.1% @ 300-595 & 625-1000 nm, Tavg > 95% @ 605-615 nm, AOI = 0°;

[0014] The spectral parameters of the dichroic film are Tavg<0.1%@560-590nm, Tavg>95%@605-700nm, and AOI=22.5°. The excitation and emission light are separated. The dichroic film has a high transition band steepness between the excitation and emission light wavelengths and a small polarization separation. The separation between P and S light at the T=50% position is less than 5nm.

[0015] The spectral parameters of the excitation light reflective film are R>99.9%@550-600nm and AOI=22.5°;

[0016] The spectral index of the dichroic antireflective film is R<0.1%@550-700nm;

[0017] Where R represents reflectivity, Tavg is the average value of transmitted light, and AOI is the angle of incidence of light.

[0018] Specifically, the excitation light filter film layer has 88 layers, which are arranged from the inside out on the right-angled surface as follows: 1.2716H, 1.568L, 1.5421H, 1.5776L, 1.557H, 1.7565L, 1.8526H, 1.7287L, 1.2828H, 1.4874L, 1.6678H, 1.447L, 1.5363H, 1.3479L, 1.3082H, 1.7617L, 1.3706H, 1.5759L, 1.2372H, 1.1118L, 0.9369 H, 0.7703L, 1.9221H, 1.349L, 1.1862H, 1.9584L, 1.6092H, 0.2435L, 1.3743H, 1.6527L, 0.9783H, 1.1148L, 0.9677H, 0. 8877L, 1.3103H, 0.352L, 0.9255H, 2.4124L, 1.2062H, 0.5817L, 0.8118H, 1.0763L, 0.8702H, 0.4394L, 1.2241H, 0.9193L , 1.0391H, 0.9871L, 0.9851H, 4.0693L, 0.9903H, 0.9266L, 0.9201H, 1.1109L, 1.0113H, 0.8056L, 1.2826H, 1.4169L, 0. 2706H, 2.485L, 0.5806H, 1.221L, 1.1237H, 0.791L, 0.8298H, 0.8265L, 2.7449H, 0.4812L, 0.8269H, 0.7995L, 0.2967H, 0 The wavelengths are 0.1075L, 1.4067H, 0.8102L, 0.8397H, 0.7284L, 0.5211H, 0.6814L, 0.7261H, 0.8117L, 0.7725H, 0.8345L, 0.547H, 0.5699L, 0.8919H, 0.895L, 0.362H, and 0.3906L, where +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this filter film is 580nm. The excitation light filter film exhibits very high transmittance, a high OD value in the cutoff band with a wide cutoff spectral range, high cutoff and high transmittance steepness, and a transition band less than 5nm, effectively eliminating stray light and improving the signal-to-noise ratio.

[0019] Specifically, the light-emitting filter film layer on the right-angled surface three has 80 layers, and the layers on the right-angled surface three, from the inside out, are as follows: 1.413H, 2.0364L, 1.2132H, 1.5495L, 1.3852H, 1.1378L, 1.347H, 1.4191L, 1.4781H, 2.0544L, 1.234H, 1.2174L, 1.3037H, 2.1689L, 1.1659H, 1.5124L, 1.2654H, 1.3928... L, 1.3638H, 1.2815L, 1.7526H, 1.6572L, 1.3798H, 0.9595L, 0.898H, 1.0977L, 1.0485H, 1.0925L, 1.0788H, 1.81 01L, 0.8748H, 1.1771L, 1.1305H, 1.0184L, 1.2069H, 1.2305L, 1.1749H, 1.074L, 0.8835H, 0.9837L, 0.9999H, 4.0 481L, 0.9643H, 0.9773L, 0.9282H, 0.9484L, 1.0364H, 0.888L, 0.8743H, 0.8607L, 1.0672H, 2.1305L, 0.8813H, 0 .9667L, 1.1332H, 0.7679L, 0.8763H, 1.1225L, 2.1527H, 0.7253L, 0.5878H, 0.8633L, 0.7981H, 0.6816L, 0.5206H The values ​​are 0.5654L, 0.7447H, 0.7502L, 0.7608H, 0.7614L, 0.5151H, 0.5987L, 0.7664H, 0.8236L, 0.6664H, 0.5471L, 0.6631H, 0.5849L, 0.722H, and 0.2051L, where +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this filter film is 610nm. The emitted light filter film exhibits very high transmittance, a high OD value in the cutoff band with a wide cutoff spectral range, high cutoff and high transmittance steepness, and a transition band less than 5nm, effectively eliminating stray light and improving the signal-to-noise ratio.

[0020] Specifically, the dichroic film layer has 66 layers, and the layers on the inclined plane three, from the inside to the outside, are as follows: 1.4156H, 0.7894M, 0.8151L, 0.709H, 1.1438M, 0.9096L, 0.8894H, 1.0189M, 1.0159L, 0.97H, 0.9631M, 1.0937L, 0.8545H, 0.9338M, 1.2L, 0.8654H, 0.9 008M, 1.2355L, 0.8725H, 0.8617M, 1.2403L, 0.9659H, 0.7915M, 1.2882L, 0.9617H, 0.7484M, 1.32 89L, O.9567H, 0.7989M, 1.2919L, 0.9315H, 0.7803M, 1.3035L, 0.9372H, 0.8168M, 1.2885L, 0.919 2H, 0.7395M, 1.3424L, 0.9872H, 0.8217M, 1.2659L, 0.97H, 0.8039M, 1.2564L, 0.8712H, 0.9214M, 1.2066L, 0.9652H, 0.8445M, 1.1731L, 0.9831H, 0.833M, 1.2382L, 0.9507H, 0.9954M, 1.0114L, 0. The parameters are 8649H, 1.1145M, 0.9558L, 0.8334H, 0.9915M, 0.9183L, 1.0204H, 0.9148M, and 0.9507L, where +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, +M represents an Al2O3 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this filter film is 810 nm. The dichroic film exhibits a high transition steepness between the excitation and emission wavelengths, with minimal polarization separation; the separation between P-beam and S-beam at the T=50% position is less than 5 nm. This effectively separates the excitation and emission light.

[0021] Specifically, the thickness of the single-layer SiO2 thin film is 200-300 nm.

[0022] Specifically, the excitation light reflective film has 30 layers, including H and L layers stacked alternately from the inside to the outside on the inclined plane. The value +H represents a TiO2 layer with a thickness of 1 / 4 wavelength optical thickness, and the value +L represents a SiO2 layer with a thickness of 1 / 4 wavelength optical thickness. The center wavelength of the reflective film is 600nm. The reflective film adopts a regular structure design and has ultra-high reflectivity.

[0023] Specifically, a two-color antireflective coating is also deposited on the second right-angled surface. This two-color antireflective coating has four layers, with the following values ​​from the inside out on the second right-angled surface: 0.4047H, 0.3888L, 0.775H, and 1.1454L. Here, +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this antireflective film is 600 nm. This antireflective film has a reflectivity of less than 0.1% in the 550-700 nm spectrum, maximizing the transmission intensity of both excitation and emission light.

[0024] Specifically, the materials of the pentagonal prism and wedge are K9 glass, BK7 glass, or fused silica FS.

[0025] Specifically, the pentagonal prism and wedge are bonded together using a high-density adhesive.

[0026] The fluorescence detection system with the bidirectional beam splitter includes a laser source, the bidirectional beam splitter, and a detector.

[0027] The laser source is located on one side of the right-angled face of the pentagonal prism, so that the light from the laser source is incident perpendicularly onto the right-angled face of the pentagonal prism.

[0028] The detector is located on one side of the right-angled surface three of the wedge plate and is used to receive and detect the light emitted from the bidirectional beam splitter.

[0029] In use, the sample to be tested is placed on one side of the right-angled face two of the pentagonal prism. The laser source is incident perpendicularly on the right-angled face one of the pentagonal prism, which is coated with an excitation light filter film. The light is reflected by the inclined face one of the pentagonal prism, which is coated with an excitation light reflection film, to the inclined face three, which is coated with a dichroic film. At this time, the laser enters the dichroic film at an incident angle of 22.5°, is reflected from the dichroic film, and then incident perpendicularly through the right-angled face two of the pentagonal prism and perpendicularly into the sample to be tested. The fluorescence generated by the sample after laser excitation passes sequentially through the right-angled face two of the pentagonal prism, through the inclined face three of the dichroic film at an incident angle of 22.5°, and then through the emission filter film on the wedge plate into the detector for corresponding detection and analysis.

[0030] Compared with the prior art, the beneficial effects of the present invention are:

[0031] The dichroic beam splitter of this invention integrates the traditional excitation light filter, emission light filter, and dichroic dichroic film into a single device, simplifying the assembly structure and improving assembly precision. By using a low incident angle of 22.5° instead of the traditional 45° incident angle, the polarization effect of the light source is reduced without altering the original optical path.

[0032] The bidirectional dichroic film designed with three types of film materials (high, medium, and low) has a high transition band steepness between the excitation and emission wavelengths, small polarization separation, and a separation of less than 5 nm between P-light and S-light at the T=50% position, effectively separating excitation light and fluorescence.

[0033] The fluorescence detection system of the present invention has a narrow-band filter film with high cutoff and narrow bandwidth coated on both the laser incident surface and the fluorescence emitting surface. The excitation light filter film and the emission light filter film have very high transmittance, the cutoff band has a high OD value and a wide cutoff band spectral range, the cutoff and high transmittance steepness is high, the transition band is less than 5nm, and the light transmission bandwidth is less than 15nm, which effectively eliminates stray light and improves the signal-to-noise ratio.

[0034] The bonding surface and wedge bevel of the pentagonal prism are coated with a SiO2 film, which facilitates the deepening of photoresist, replaces the conventional photosensitive adhesive bonding process, and improves the laser damage threshold of the bonding surface. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the laser-induced fluorescence detection system device described in this invention.

[0036] Figure 2 This is a schematic diagram of each film layer of the pentagonal prism described in this invention.

[0037] Figure 3 This is a schematic diagram of the excitation light filter film of the present invention.

[0038] Figure 4 This is a schematic diagram of the emission light filter film of the present invention.

[0039] Figure 5 This is a schematic diagram of the spectrum of the bidirectional spectrophotometer of the present invention.

[0040] Figure 6 This is a schematic diagram of the excitation light reflection film of the present invention.

[0041] Figure 7 This is a schematic diagram of the spectrum of the two-color antireflection film of the present invention.

[0042] Figure 8 This is a schematic diagram of an existing fluorescence detection system.

[0043] Specific implementation examples

[0044] The following is in conjunction with the instruction manual appendix. Figures 1-5 The technical solution of the present invention will be described in detail below.

[0045] like Figure 1 As shown, the bidirectional beam splitter of this embodiment includes a pentagonal prism 2.1 and a wedge plate 2.2, both with the same refractive index.

[0046] The pentagonal prism 2.1 is composed of right-angled surface 1 2.11, right-angled surface 2.12, inclined surface 1 2.13, inclined surface 2.14, and inclined surface 3 2.15. Right-angled surface 1 2.11 and right-angled surface 2.12 are connected perpendicularly to each other. One edge of inclined surface 1 2.13 is connected to right-angled surface 2.12, and the angle between them is 112.5°. One edge of inclined surface 3 2.15 is connected to the incident right-angled surface 2.11, and the angle between them is 112.5°. The two edges of inclined surface 2.14 are connected to the other edges of inclined surface 1 2.13 and inclined surface 3 2.15, respectively, and the angle between adjacent inclined surfaces is 112.5°.

[0047] The wedge plate 2.2 is composed of inclined plane 2.21, right-angled plane 2.22 forming a 22.5° angle with inclined plane 2.21, and right-angled plane 2.23 forming a 67.5° angle with inclined plane 2.21.

[0048] An excitation light filter layer 2.3 is deposited on the right-angled surface 1 2.11, a two-color anti-reflection film layer 2.4 is deposited on the right-angled surface 2.12, an excitation light reflection film layer 2.5 is deposited on the inclined surface 1 2.13, and a two-dimensional color separation film layer 2.6 is deposited on the inclined surface 3 2.15.

[0049] After a single-layer SiO2 thin film layer 2.7 is deposited on the inclined surface 2.21 of the wedge plate 2.2, it is bonded to the inclined surface 2.15 which is deposited with a dihedral color separation film layer 2.6. An emission light filter film layer 2.8 is deposited on the right-angle surface 2.22.

[0050] Specifically, the spectral parameters of the excitation light filter layer 2.3 are: Tavg < 0.1% @ 300-565 & 595-1000 nm, Tavg > 95% @ 575-585 nm, and AOI = 0°;

[0051] The spectral properties of the light-emitting filter layer 2.8 are: Tavg < 0.1% @ 300-595 & 625-1000 nm, Tavg > 95% @ 605-615 nm, AOI = 0°;

[0052] The spectral parameters of the dichroic film layer 2.6 are Tavg<0.1%@560-590nm, Tavg>95%@605-700nm, and AOI=22.5°. It separates the excitation light and the emission light. The dichroic film has a high transition band steepness between the excitation light wavelength and the emission light wavelength, and small polarization separation. The separation between P light and S light at the T=50% position is less than 5nm.

[0053] The spectral properties of the excitation light reflective film layer 2.5 are R>99.9%@550-600nm and AOI=22.5°;

[0054] The spectral index of the dichroic antireflective film layer 2.4 is R<0.1%@550-700nm;

[0055] Where R represents reflectivity, Tavg is the average value of transmitted light, and AOI is the angle of incidence of light.

[0056] In this embodiment, the excitation light filter layer 2.3 has 88 layers, which are arranged from the inside out on the right-angled surface 2.11 as follows: 1.2716H, 1.568L, 1.5421H, 1.5776L, 1.557H, 1.7565L, 1.8526H, 1.7287L, 1.2828H, 1.4874L, 1.6678H, 1.447L, 1.5363H, 1.3479L, 1.3082H, 1.7617L, 1.3706H, 1.5759L, 1.2372H, 1.1118L, 0. 9369H, 0.7703L, 1.9221H, 1.349L, 1.1862H, 1.9584L, 1.6092H, 0.2435L, 1.3743H, 1.6527L, 0.9783H, 1.1148L, 0.9677H , 0.8877L, 1.3103H, 0.352L, 0.9255H, 2.4124L, 1.2062H, 0.5817L, 0.8118H, 1.0763L, 0.8702H, 0.4394L, 1.2241H, 0.91 93L, 1.0391H, 0.9871L, 0.9851H, 4.0693L, 0.9903H, 0.9266L, 0.9201H, 1.1109L, 1.0113H, 0.8056L, 1.2826H, 1.4169L, 0.2706H, 2.485L, 0.5806H, 1.221L, 1.1237H, 0.791L, 0.8298H, 0.8265L, 2.7449H, 0.4812L, 0.8269H, 0.7995L, 0.2967H The wavelengths are 0.1075L, 1.4067H, 0.8102L, 0.8397H, 0.7284L, 0.5211H, 0.6814L, 0.7261H, 0.8117L, 0.7725H, 0.8345L, 0.547H, 0.5699L, 0.8919H, 0.895L, 0.362H, and 0.3906L, where +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this filter film is 580nm. A schematic diagram of the laser filter film spectrum is shown below. Figure 3As shown in the figure, the laser filter film has a Tavg < 0.1% @ 300-565 & 595-1000nm, a Tavg > 95% @ 575-585nm, and an AOI of 0°. The excitation light filter film exhibits very high transmittance, a high OD value at the cutoff band with a wide cutoff spectral range, high cutoff and high transmittance steepness, and a transition band less than 5nm, effectively eliminating stray light and improving the signal-to-noise ratio.

[0057] In this embodiment, the light-emitting filter layer 2.8 on the right-angled surface 2.22 has 80 layers. The layers on the right-angled surface 2.22, from the inside out, are: 1.413H, 2.0364L, 1.2132H, 1.5495L, 1.3852H, 1.1378L, 1.347H, 1.4191L, 1.4781H, 2.0544L, 1.234H, 1.2174L, 1.3037H, 2.1689L, 1.1659H, 1.5124L, 1.265... 4H, 1.3928L, 1.3638H, 1.2815L, 1.7526H, 1.6572L, 1.3798H, 0.9595L, 0.898H, 1.0977L, 1.0485H, 1.0925L, 1.078 8H, 1.8101L, 0.8748H, 1.1771L, 1.1305H, 1.0184L, 1.2069H, 1.2305L, 1.1749H, 1.074L, 0.8835H, 0.9837L, 0.999 9H, 4.0481L, 0.9643H, 0.9773L, 0.9282H, 0.9484L, 1.0364H, 0.888L, 0.8743H, 0.8607L, 1.0672H, 2.1305L, 0.881 3H, 0.9667L, 1.1332H, 0.7679L, 0.8763H, 1.1225L, 2.1527H, 0.7253L, 0.5878H, 0.8633L, 0.7981H, 0.6816L, 0.52 The wavelengths are 0.6H, 0.5654L, 0.7447H, 0.7502L, 0.7608H, 0.7614L, 0.5151H, 0.5987L, 0.7664H, 0.8236L, 0.6664H, 0.5471L, 0.6631H, 0.5849L, 0.722H, and 0.2051L, where +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this filter film is 610nm. A schematic diagram of the emission light filter film layer is shown in Figure 2.8. Figure 4As shown in the figure, Tavg < 0.1% @ 300-595 & 625-1000nm, Tavg > 95% @ 605-615nm, and AOI = 0°. The emission filter film has very high transmittance, a high OD value in the cutoff band, a wide cutoff spectral range, high cutoff and high transmittance steepness, and a transition band of less than 5nm, effectively eliminating stray light and improving the signal-to-noise ratio.

[0058] The dichroic film layer 2.6 described in this embodiment has 66 layers. The layers, from the inside to the outside on the inclined plane 2.15, are: 1.4156H, 0.7894M, 0.8151L, 0.709H, 1.1438M, 0.9096L, 0.8894H, 1.0189M, 1.0159L, 0.97H, 0.9631M, 1.0937L, 0.8545H, 0.9338M, 1.2L, 0.865 4H, 0.9008M, 1.2355L, 0.8725H, 0.8617M, 1.2403L, 0.9659H, 0.7915M, 1.2882L, 0.9617H, 0.7484M , 1.3289L, O.9567H, 0.7989M, 1.2919L, 0.9315H, 0.7803M, 1.3035L, 0.9372H, 0.8168M, 1.2885L, 0 .9192H, 0.7395M, 1.3424L, 0.9872H, 0.8217M, 1.2659L, 0.97H, 0.8039M, 1.2564L, 0.8712H, 0.921 4M, 1.2066L, 0.9652H, 0.8445M, 1.1731L, 0.9831H, 0.833M, 1.2382L, 0.9507H, 0.9954M, 1.0114L, The wavelengths are 0.8649H, 1.1145M, 0.9558L, 0.8334H, 0.9915M, 0.9183L, 1.0204H, 0.9148M, and 0.9507L, where +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, +M represents an Al2O3 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this filter film is 810nm. A schematic diagram of the spectrum of this dichroic film layer 2.6 is shown below. Figure 5 As shown in the figure, it can be seen that Tavg<0.1%@560-590nm, Tavg>95%@605-700nm, and AOI=22.5°. This filter film can separate the excitation light and the emission light. The dichroic film has a high transition band steepness between the excitation source wavelength and the emission source wavelength, and small polarization separation. The separation between P light and S light at the T=50% position is less than 5nm.

[0059] Specifically, the thickness of the single-layer SiO2 thin film 2.7 is 200-300 nm.

[0060] Specifically, the excitation light reflective film layer 2.5 has 30 layers, including H and L layers stacked alternately from the inside to the outside on the inclined plane 2.13. The value +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and the value +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this reflective film is 600 nm. A schematic diagram of the spectrum of the excitation light reflective film layer 2.5 is shown below. Figure 6 As shown in the figure, R>99.9%@550-600nm, AOI=22.5°. This reflective film adopts a regular structure design and has ultra-high reflectivity.

[0061] Specifically, the dichroic antireflective film 2.4 has four layers, and the layers, from the inside to the outside on the right-angled plane 2.12, are: 0.4047H, 0.3888L, 0.775H, and 1.1454L. Here, +H represents a TiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness, and +L represents a SiO2 layer with a thickness corresponding to 1 / 4 wavelength optical thickness. The center wavelength of this antireflective film is 600 nm. A schematic diagram of the spectrum of the dichroic antireflective film 2.4 is shown below. Figure 7 As shown in the figure, the antireflective coating has a reflectivity of less than 0.1% in the 550-700nm spectrum, which greatly increases the transmittance of excitation and emission light.

[0062] Specifically, the materials of the pentagonal prism 2.1 and the wedge plate 2.2 are K9 glass, BK7 glass or fused silica FS.

[0063] Specifically, the pentagonal prism 2.1 and the wedge plate 2.2 are bonded together using a deep-bonding adhesive.

[0064] like Figure 2 As shown, the fluorescence detection system with the dihedral beam splitter includes a laser source 1, the dihedral beam splitter 2, and a detector 3.

[0065] Among them, the laser source 1 is located on one side of the right angle face 2.11 of the pentagonal prism 2.1, so that the light from the laser source 1 is incident perpendicularly onto the right angle face 2.11 of the pentagonal prism 2.1.

[0066] The detector 3 is located on one side of the right angle surface 2.22 of the wedge plate 2.2, and is used to receive and detect the light emitted from the dihedral beam splitter 2.

[0067] In use, the sample to be tested is placed on one side of the right-angled face 2.12 of the pentagonal prism 2.1. The laser source is incident perpendicularly on the right-angled face 2.11 of the pentagonal prism, which is coated with an excitation light filter layer 2.3. The light is reflected by the inclined face 2.13 of the pentagonal prism, which is coated with an excitation light reflection layer 2.5, to the inclined face 2.15 of the dichroic film layer 2.6. At this time, the laser enters the dichroic film layer 2.6 at an incident angle of 22.5°, is reflected from the dichroic film layer 2.6, and then is incident perpendicularly through the right-angled face 2.12 of the pentagonal prism and enters the sample to be tested. The fluorescence generated by the laser excitation of the sample 4 passes sequentially through the right-angled face 2.12 of the pentagonal prism, through the inclined face 2.15 of the dichroic film layer 2.6 at an incident angle of 22.5°, and then through the emission filter layer 2.8 on the wedge plate 2.2 to enter the detector for corresponding detection and analysis.

[0068] The above specific embodiments are only explained in detail for a certain laser wavelength as a technical solution. This invention is not limited to the above embodiments. Any improvement or substitution based on the principles of this invention should be within the protection scope of this invention.

Claims

1. A two-dimensional beam splitter, comprising a pentagonal prism (2.1) and a wedge plate (2.2) of the same refractive index, characterized in that: The five prism faces of the pentagonal prism (2.1) are composed of right-angle face one (2.11), right-angle face two (2.12), inclined face one (2.13), inclined face two (2.14), and inclined face three (2.15). Right-angle face one (2.11) is the incident right-angle face and is perpendicularly connected to right-angle face two (2.12). One edge of inclined face one (2.13) is connected to right-angle face two (2.12) and the included angle between them is 112.5°. One edge of inclined face three (2.15) is connected to right-angle face one (2.11) and the included angle between them is 112.5°. The two edges of inclined face two (2.14) are connected to the other edges of inclined face one (2.13) and inclined face three (2.15) respectively, and the included angle between adjacent inclined faces is 112.5°. The wedge plate (2.2) is composed of inclined plane four (2.21), right-angled plane three (2.22) forming an angle of 22.5° with inclined plane four (2.21), and right-angled plane four (2.23) forming an angle of 67.5° with inclined plane four (2.21). An excitation light filter film (2.3) is deposited on the right-angled surface one (2.11), an excitation light reflection film (2.5) is deposited on the inclined surface one (2.13), and a dichroic film (2.6) is deposited on the inclined surface three (2.15). A single-layer SiO2 thin film (2.7) is deposited on the inclined surface four (2.21) of the wedge plate (2.2) and then bonded to the inclined surface three (2.15) which is deposited with a dihedral color separation film (2.6). An emission light filter film (2.8) is deposited on the right-angled surface three (2.22), and the right-angled surface three (2.22) is parallel to the right-angled surface two (2.12). The excitation light filter film (2.3) has the following spectral parameters: Tavg < 0.1% @ 300-565 & 595-1000 nm, Tavg > 95% @ 575-585 nm, and AOI = 0°. The spectral parameters of the light emission filter layer (2.8) are: Tavg<0.1%@300-595&625-1000nm, Tavg>95%@605-615nm, AOI=0°; The spectral parameters of the dichroic film layer (2.6) are: Tavg<0.1%@560-590nm, Tavg>95%@605-700nm, and AOI=22.5°; The spectral properties of the excitation light reflective film (2.5) are R>99.9%@550-600nm and AOI=22.5°; Where R represents reflectivity, Tavg is the average value of transmitted light, and AOI is the angle of incidence of light. The excitation light filter layer (2.3) has 88 layers, which are arranged from the inside to the outside on right-angled surface (2.11) as follows: 1.2716H, 1.568L, 1.5421H, 1.5776L, 1.557H, 1.7565L, 1.8526H, 1.7287L, 1.2828H, 1.4874L, 1.6678H, 1.447L, 1.5363H, 1.3479L, 1.3082H, 1.7617L, 1.3706H, 1.5759L, 1.2372... H, 1.1118L, 0.9369H, 0.7703L, 1.9221H, 1.349L, 1.1862H, 1.9584L, 1.6092H, 0.2435L, 1.3743H, 1.6527L, 0.9783 H, 1.1148L, 0.9677H, 0.8877L, 1.3103H, 0.352L, 0.9255H, 2.4124L, 1.2062H, 0.5817L, 0.8118H, 1.0763L, 0.8702 H, 0.4394L, 1.2241H, 0.9193L, 1.0391H, 0.9871L, 0.9851H, 4.0693L, 0.9903H, 0.9266L, 0.9201H, 1.1109L, 1.011 3H, 0.8056L, 1.2826H, 1.4169L, 0.2706H, 2.485L, 0.5806H, 1.221L, 1.1237H, 0.791L, 0.8298H, 0.8265L, 2.7449H , 0.4812L, 0.8269H, 0.7995L, 0.2967H, 0.1075L, 1.4067H, 0.8102L, 0.8397H, 0.7284L, 0.5211H, 0.6814L, 0.7261H, 0.8117L, 0.7725H, 0.8345L, 0.547H, 0.5699L, 0.8919H, 0.895L, 0.362H, 0.3906L, where the value +H represents a TiO2 layer with a corresponding 1 / 4 wavelength optical thickness, and the value +L represents a SiO2 layer with a corresponding 1 / 4 wavelength optical thickness. The center wavelength of this excitation light filter film layer (2.3) is 580nm; The light-emitting filter layer (2.8) on the right-angled surface three (2.22) has 80 layers, and the layers on the right-angled surface three (2.22) from the inside out are: 1.413H, 2.0364L, 1.2132H, 1.5495L, 1.3852H, 1.1378L, 1.347H, 1.4191L, 1.4781H, 2.0544L, 1.234H, 1.2174L, 1.3037H, 2.1689L, 1.1659H, 1 .5124L, 1.2654H, 1.3928L, 1.3638H, 1.2815L, 1.7526H, 1.6572L, 1.3798H, 0.9595L, 0.898H, 1.0977L, 1.04 85H, 1.0925L, 1.0788H, 1.8101L, 0.8748H, 1.1771L, 1.1305H, 1.0184L, 1.2069H, 1.2305L, 1.1749H, 1.074L ,0.8835H,0.9837L,0.9999H,4.0481L,0.9643H,0.9773L,0.9282H,0.9484L,1.0364H,0.888L,0.8743H,0 .8607L, 1.0672H, 2.1305L, 0.8813H, 0.9667L, 1.1332H, 0.7679L, 0.8763H, 1.1225L, 2.1527H, 0.7253L, 0.5 878H, 0.8633L, 0.7981H, 0.6816L, 0.5206H, 0.5654L, 0.7447H, 0.7502L, 0.7608H, 0.7614L, 0.5151H, 0.5987L, 0.7664H, 0.8236L, 0.6664H, 0.5471L, 0.6631H, 0.5849L, 0.722H, 0.2051L, where the value +H represents a TiO2 layer with a corresponding optical thickness of 1 / 4 wavelength, and the value +L represents a SiO2 layer with a corresponding optical thickness of 1 / 4 wavelength. The center wavelength of this light-emitting filter layer (2.8) is 610nm. The dichroic film layer (2.6) has 66 layers, and the layers on the inclined plane (2.15) from the inside out are: 1.4156H, 0.7894M, 0.8151L, 0.709H, 1.1438M, 0.9096L, 0.8894H, 1.0189M, 1.0159L, 0.97H, 0.9631M, 1.0937L, 0.8545H, 0 .9338M, 1.2L, 0.8654H, 0.9008M, 1.2355L, 0.8725H, 0.8617M, 1.2403L, 0.9659H, 0.791 5M, 1.2882L, 0.9617H, 0.7484M, 1.3289L, O.9567H, 0.7989M, 1.2919L, 0.9315H, 0.7803M , 1.3035L, 0.9372H, 0.8168M, 1.2885L, 0.9192H, 0.7395M, 1.3424L, 0.9872H, 0.8217M, 1.2659L, 0.97H, 0.8039M, 1.2564L, 0.8712H, 0.9214M, 1.2066L, 0.9652H, 0.8445M, 1.17 31L, 0.9831H, 0.833M, 1.2382L, 0.9507H, 0.9954M, 1.0114L, 0.8649H, 1.1145M, 0.9558L, 0.8334H, 0.9915M, 0.9183L, 1.0204H, 0.9148M, 0.9507L, where +H represents a TiO2 layer with a thickness of 1 / 4 wavelength, +M represents an Al2O3 layer with a thickness of 1 / 4 wavelength, and +L represents a SiO2 layer with a thickness of 1 / 4 wavelength. The center wavelength of this dichroic film layer (2.6) is 810nm.

2. The bidirectional beam splitter according to claim 1, characterized in that: The thickness of the single-layer SiO2 thin film (2.7) is 200-300 nm.

3. The dihedral beam splitter according to claim 1, characterized in that: The excitation light reflective film layer (2.5) has 30 layers, including H and L layers stacked alternately from the inside to the outside on the inclined plane (2.13), where the value +H represents a TiO2 layer with a thickness of 1 / 4 wavelength optical thickness, and the value +L represents a SiO2 layer with a thickness of 1 / 4 wavelength optical thickness. The center wavelength of the excitation light reflective film layer (2.5) is 600nm. A two-color antireflective coating (2.4) is also deposited on the right-angled surface (2.12). The spectral index of the two-color antireflective coating (2.4) is R<0.1%@550-700nm. The two-color antireflective coating (2.4) has 4 layers. The layers on the right-angled surface (2.12) from the inside out are: 0.4047H, 0.3888L, 0.775H, and 1.1454L. The value +H represents the TiO2 layer with a thickness of 1 / 4 wavelength optical thickness, and the value +L represents the SiO2 layer with a thickness of 1 / 4 wavelength optical thickness. The center wavelength of the two-color antireflective coating (2.4) is 600nm.

4. The bidirectional beam splitter according to claim 1, characterized in that: The pentagonal prism (2.1) and wedge (2.2) are made of K9 glass, BK7 glass or fused silica FS.

5. The bidirectional beam splitter according to claim 1, characterized in that: The pentagonal prism (2.1) and the wedge (2.2) are bonded together using a deep-bonded adhesive.

6. A fluorescence detection system, characterized in that: It includes a laser source (1), a dihedral beam splitter (2) as described in any one of claims 1-5, and a detector (3). Among them, the laser source (1) is located on one side of the right angle face (2.11) of the pentagonal prism (2.1), and the light from the laser source (1) is incident perpendicularly on the right angle face (2.11) of the pentagonal prism (2.1); The detector (3) is located on one side of the right angle face three (2.22) of the wedge plate (2.2) and is used to receive and detect the light emitted from the dihedral beam splitter (2).

Images