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An ultra-compact (54 × 58 × 8.5 mm) and wide-aperture (1 × 7 mm) nine-color spectrometer was developed, “split in two” by an array of ten dichroic mirrors, which was used for instantaneous spectral imaging. The incident light flux with a cross section smaller than the aperture size is divided into a continuous strip 20 nm wide and nine color fluxes with central wavelengths of 530, 550, 570, 590, 610, 630, 650, 670 and 690 nm. Images of nine color streams are simultaneously efficiently measured by the image sensor. Unlike conventional dichroic mirror arrays, the developed dichroic mirror array has a unique two-piece configuration, which not only increases the number of colors that can be measured simultaneously, but also improves image resolution for each color stream. The developed nine-color spectrometer is used for four-capillary electrophoresis. Simultaneous quantitative analysis of eight dyes migrating simultaneously in each capillary using nine-color laser-induced fluorescence. Since the nine-color spectrometer is not only ultra-small and inexpensive, but also has high luminous flux and sufficient spectral resolution for most spectral imaging applications, it can be widely used in various fields.
Hyperspectral and multispectral imaging has become an important part of astronomy2, remote sensing for Earth observation3,4, food and water quality control5,6, art conservation and archeology7, forensics8, surgery9, biomedical analysis and diagnostics10,11 etc. Field 1 An indispensable technology ,12,13. Methods for measuring the spectrum of light emitted by each point of emission in the field of view are divided into (1) point scanning (“broom”)14,15, (2) linear scanning (“panicle”)16,17,18, (3) length scans waves19,20,21 and (4) images22,23,24,25. In the case of all these methods, spatial resolution, spectral resolution and temporal resolution have a trade-off relationship9,10,12,26. In addition, light output has a significant impact on sensitivity, i.e. the signal-to-noise ratio in spectral imaging26. The luminous flux, that is, the efficiency of using light, is directly proportional to the ratio of the actual measured amount of light of each luminous point per unit time to the total amount of light of the measured wavelength range. Category (4) is an appropriate method when the intensity or spectrum of light emitted by each emitting point changes with time or when the position of each emitting point changes with time because the spectrum of light emitted by all emitting points is measured simultaneously. 24.
Most of the above methods are combined with large, complex and/or expensive spectrometers using 18 gratings or 14, 16, 22, 23 prisms for classes (1), (2) and (4) or 20, 21 filter disks, liquid filters. Crystalline tunable filters (LCTF)25 or acousto-optic tunable filters (AOTF)19 of category (3). In contrast, category (4) multi-mirror spectrometers are small and inexpensive due to their simple configuration27,28,29,30. In addition, they have a high luminous flux because the light shared by each dichroic mirror (that is, the transmitted and reflected light of the incident light on each dichroic mirror) is fully and continuously used. However, the number of wavelength bands (i.e. colors) that must be measured simultaneously is limited to about four.
Spectral imaging based on fluorescence detection is commonly used for multiplex analysis in biomedical detection and diagnostics 10, 13 . In multiplexing, since multiple analytes (eg, specific DNA or proteins) are labeled with different fluorescent dyes, each analyte present at each emission point in the field of view is quantified using multicomponent analysis. 32 breaks down the detected fluorescence spectrum emitted by each emission point. During this process, different dyes, each emitting a different fluorescence, can colocalize, that is, coexist in space and time. Currently, the maximum number of dyes that can be excited by a single laser beam is eight33. This upper limit is not determined by the spectral resolution (i.e., number of colors), but by the width of the fluorescence spectrum (≥50 nm) and the amount of dye Stokes shift (≤200 nm) at FRET (using FRET)10. However, the number of colors must be greater than or equal to the number of dyes to eliminate the spectral overlap of mixed dyes31,32. Therefore, it is necessary to increase the number of simultaneously measured colors to eight or more.
Recently, an ultra-compact heptachroic spectrometer (using an array of heptychroic mirrors and an image sensor to measure four fluorescent fluxes) has been developed. The spectrometer is two to three orders of magnitude smaller than conventional spectrometers using gratings or prisms34,35. However, it is difficult to place more than seven dichroic mirrors in a spectrometer and simultaneously measure more than seven colors36,37. With an increase in the number of dichroic mirrors, the maximum difference in the lengths of the optical paths of dichroic light fluxes increases, and it becomes difficult to display all light fluxes on one sensory plane. The longest optical path length of the light flux also increases, so the width of the spectrometer aperture (i.e. the maximum width of the light analyzed by the spectrometer) decreases.
In response to the above problems, an ultra-compact nine-color spectrometer with a two-layer “dichroic” decachromatic mirror array and an image sensor for instantaneous spectral imaging [category (4)] was developed. Compared to previous spectrometers, the developed spectrometer has a smaller difference in the maximum optical path length and a smaller maximum optical path length. It has been applied to four-capillary electrophoresis to detect laser-induced nine-color fluorescence and to quantify the simultaneous migration of eight dyes in each capillary. Since the developed spectrometer is not only ultra-small and inexpensive, but also has a high luminous flux and sufficient spectral resolution for most spectral imaging applications, it can be widely used in various fields.
The traditional nine-color spectrometer is shown in fig. 1a. Its design follows that of the previous ultra-small seven-color spectrometer 31. It consists of nine dichroic mirrors arranged horizontally at an angle of 45° to the right, and the image sensor (S) is located above the nine dichroic mirrors. The light entering from below (C0) is divided by an array of nine dichroic mirrors into nine light flows going up (C1, C2, C3, C4, C5, C6, C7, C8 and C9). All nine color streams are fed directly to the image sensor and are detected simultaneously. In this study, C1, C2, C3, C4, C5, C6, C7, C8, and C9 are in order of wavelength and are represented by magenta, violet, blue, cyan, green, yellow, orange, red-orange, and red, respectively. Although these color designations are used in this document, as shown in Figure 3, because they differ from the actual colors seen by the human eye.
Schematic diagrams of conventional and new nine-color spectrometers. (a) Conventional nine-color spectrometer with an array of nine dichroic mirrors. (b) New nine-color spectrometer with a two-layer dichroic mirror array. The incident light flux C0 is divided into nine colored light fluxes C1-C9 and detected by the image sensor S.
The developed new nine-color spectrometer has a two-layer dichroic mirror grating and an image sensor, as shown in Fig. 1b. In the lower tier, five dichroic mirrors are tilted 45° to the right, aligned to the right from the center of the array of decamers. At the top level, five additional dichroic mirrors are tilted 45° to the left and located from the center to the left. The leftmost dichroic mirror of the lower layer and the rightmost dichroic mirror of the upper layer overlap each other. The incident light flux (C0) is divided from below into four outgoing chromatic fluxes (C1-C4) by five dichroic mirrors on the right and five outgoing chromatic fluxes (C5-C4) by five dichroic mirrors on the left C9). Like conventional nine-color spectrometers, all nine color streams are directly injected into the image sensor (S) and detected simultaneously. Comparing Figures 1a and 1b, one can see that in the case of the new nine-color spectrometer, both the maximum difference and the longest optical path length of the nine color fluxes are halved.
The detailed construction of an ultra-small two-layer dichroic mirror array 29 mm (width) × 31 mm (depth) × 6 mm (height) is shown in Figure 2. The decimal dichroic mirror array consists of five dichroic mirrors on the right (M1-M5) and five dichroic mirrors on the left ( M6-M9 and another M5), each dichroic mirror is fixed in the upper aluminum bracket. All dichroic mirrors are staggered to compensate for parallel displacement due to refraction of the flow through the mirrors. Below M1, a band-pass filter (BP) is fixed. M1 and BP dimensions are 10mm (long side) x 1.9mm (short side) x 0.5mm (thickness). The dimensions of the remaining dichroic mirrors are 15 mm × 1.9 mm × 0.5 mm. The matrix pitch between M1 and M2 is 1.7 mm, while the matrix pitch of other dichroic mirrors is 1.6 mm. On fig. 2c combines the incident light flux C0 and nine colored light fluxes C1-C9, separated by a de-chamber matrix of mirrors.
Construction of a two-layer dichroic mirror matrix. (a) A perspective view and (b) a cross-sectional view of a two-layer dichroic mirror array (dimensions 29 mm x 31 mm x 6 mm). It consists of five dichroic mirrors (M1-M5) located in the lower layer, five dichroic mirrors (M6-M9 and another M5) located in the upper layer, and a bandpass filter (BP) located below M1. (c) Cross-sectional view in vertical direction, with C0 and C1-C9 overlap.
The width of the aperture in the horizontal direction, indicated by the width C0 in Fig. 2, c, is 1 mm, and in the direction perpendicular to the plane of Fig. 2, c, given by the design of the aluminum bracket, – 7 mm. That is, the new nine-color spectrometer has a large aperture size of 1 mm × 7 mm. The optical path of C4 is the longest among C1-C9, and the optical path of C4 inside the dichroic mirror array, due to the above ultra-small size (29 mm × 31 mm × 6 mm), is 12 mm. At the same time, the optical path length of C5 is the shortest among C1-C9, and the optical path length of C5 is 5.7mm. Therefore, the maximum difference in optical path length is 6.3 mm. The above optical path lengths are corrected for the optical path length for optical transmission of M1-M9 and BP (from quartz).
The spectral properties of М1−М9 and VR are calculated so that the fluxes С1, С2, С3, С4, С5, С6, С7, С8 and С9 are in the wavelength range 520–540, 540–560, 560–580, 580–600 , 600–620, 620–640, 640–660, 660–680, and 680–700 nm, respectively.
A photograph of the manufactured matrix of decachromatic mirrors is shown in Fig. 3a. M1-M9 and BP are glued to the 45-degree slope and horizontal plane of the aluminum support, respectively, while M1 and BP are hidden on the back of the figure.
Production of an array of decan mirrors and its demonstration. (a) An array of fabricated decachromatic mirrors. (b) A 1 mm × 7 mm nine-color split image projected onto a sheet of paper placed in front of an array of decachromatic mirrors and backlit with white light. (c) An array of decochromatic mirrors illuminated with white light from behind. (d) Nine-color splitting stream emanating from the decane mirror array, observed by placing a smoke-filled acrylic canister in front of the decane mirror array at c and darkening the room.
The measured transmission spectra of M1-M9 C0 at an angle of incidence of 45° and the measured transmission spectrum of BP C0 at an angle of incidence of 0° are shown in Figs. 4a. The transmission spectra of C1-C9 relative to C0 are shown in Figs. 4b. These spectra were calculated from the spectra in Figs. 4a in accordance with the optical path C1-C9 in Fig. 4a. 1b and 2c. For example, TS(C4) = TS (BP) × [1 − TS (M1)] × TS (M2) × TS (M3) × TS (M4) × [1 − TS (M5)], TS(C9 ) = TS (BP) × TS (M1) × [1 − TS (M6)] × TS (M7) × TS (M8) × TS (M9) × [1 − TS (M5)], where TS(X) and [ 1 − TS(X)] are the transmission and reflection spectra of X, respectively. As shown in Figure 4b, the bandwidths (bandwidth ≥50%) of C1, C2, C3, C4, C5, C6, C7, C8 and C9 are 521-540, 541-562, 563-580, 581-602, 603 -623, 624-641, 642-657, 659-680 and 682-699 nm. These results are consistent with the developed ranges. In addition, the utilization efficiency of C0 light is high, that is, the average maximum C1-C9 light transmittance is 92%.
Transmission spectra of a dichroic mirror and a split nine-color flux. (a) Measured transmission spectra of M1-M9 at 45° incidence and BP at 0° incidence. (b) Transmission spectra of C1–C9 relative to C0 calculated from (a).
On fig. 3c, the array of dichroic mirrors is located vertically, so that its right side in Fig. 3a is the top side and the white beam of the collimated LED (C0) is backlit. The array of decachromatic mirrors shown in Figure 3a is mounted in a 54 mm (height) × 58 mm (depth) × 8.5 mm (thickness) adapter. On fig. 3d, in addition to the state shown in fig. 3c, a smoke-filled acrylic tank was placed in front of an array of decochromatic mirrors, with the lights in the room turned off. As a result, nine dichroic streams are visible in the tank, emanating from an array of decatroic mirrors. Each split stream has a rectangular cross section with dimensions of 1 × 7 mm, which corresponds to the aperture size of the new nine-color spectrometer. In Figure 3b, a sheet of paper is placed in front of the array of dichroic mirrors in Figure 3c, and a 1 x 7 mm image of nine dichroic streams projected onto the paper is observed from the direction of paper movement. streams. The nine color separation streams in fig. 3b and d are C4, C3, C2, C1, C5, C6, C7, C8 and C9 from top to bottom, which can also be seen in figures 1 and 2. 1b and 2c. They are observed in colors corresponding to their wavelengths. Due to the low white light intensity of the LED (see Supplementary Fig. S3) and the sensitivity of the color camera used to capture C9 (682–699 nm) in Fig. Other splitting flows are weak. Similarly, C9 was faintly visible to the naked eye. Meanwhile, C2 (the second stream from the top) looks green in Figure 3, but looks more yellow to the naked eye.
The transition from Figure 3c to d is shown in Supplementary Video 1. Immediately after the white light from the LED passes through the decachromatic mirror array, it splits simultaneously into nine color streams. In the end, the smoke in the vat gradually dissipated from top to bottom, so that the nine colored powders also disappeared from top to bottom. In contrast, in Supplementary Video 2, when the wavelength of the light flux incident on the array of decachromatic mirrors was changed from long to short in the order of 690, 671, 650, 632, 610, 589, 568, 550 and 532 nm. , Only the corresponding split streams of the nine split streams in the order of C9, C8, C7, C6, C5, C4, C3, C2, and C1 are displayed. The acrylic reservoir is replaced by a quartz pool, and the flakes of each shunted flow can be clearly observed from the sloping upward direction. In addition, the sub-video 3 is edited such that the wavelength change portion of the sub-video 2 is replayed. This is the most eloquent expression of the characteristics of a decochromatic array of mirrors.
The above results show that the manufactured decachromatic mirror array or the new nine-color spectrometer works as intended. The new nine-color spectrometer is formed by mounting an array of decachromatic mirrors with adapters directly onto the image sensor board.
Luminous flux with a wavelength range from 400 to 750 nm, emitted by four radiation points φ50 μm, located at 1 mm intervals in the direction perpendicular to the plane of Fig. 2c, respectively Researches 31, 34. The four-lens array consists of four lenses φ1 mm with a focal length of 1.4 mm and a pitch of 1 mm. Four collimated streams (four C0) are incident on the DP of a new nine-color spectrometer, spaced at 1 mm intervals. An array of dichroic mirrors divides each stream (C0) into nine color streams (C1-C9). The resulting 36 streams (four sets of C1-C9) are then injected directly into a CMOS (S) image sensor directly connected to an array of dichroic mirrors. As a result, as shown in Fig. 5a, due to the small maximum optical path difference and the short maximum optical path, the images of all 36 streams were detected simultaneously and clearly with the same size. According to the downstream spectra (see Supplementary Figure S4), the image intensity of the four groups C1, C2 and C3 is relatively low. Thirty-six images were 0.57 ± 0.05 mm in size (mean ± SD). Thus, the image magnification averaged 11.4. The vertical spacing between images averages 1 mm (same spacing as a lens array) and the horizontal spacing averages 1.6 mm (same spacing as a dichroic mirror array). Because the image size is much smaller than the distance between images, each image can be measured independently (with low crosstalk). Meanwhile, images of twenty-eight streams recorded by the conventional seven-color spectrometer used in our previous study are shown in Fig. 5 B. The array of seven dichroic mirrors was created by removing the two rightmost dichroic mirrors from the array of nine dichroic mirrors in Figure 1a. Not all images are sharp, the image size increases from C1 to C7. Twenty-eight images are 0.70 ± 0.19 mm in size. Therefore, it is difficult to maintain a high image resolution in all images. The coefficient of variation (CV) for image size 28 in Figure 5b was 28%, while the CV for image size 36 in Figure 5a decreased to 9%. The above results show that the new nine-color spectrometer not only increases the number of simultaneously measured colors from seven to nine, but also has a high image resolution for each color.
Comparison of the quality of the split image formed by conventional and new spectrometers. (a) Four groups of nine-color separated images (C1-C9) generated by the new nine-color spectrometer. (b) Four sets of seven-color separated images (C1-C7) formed with a conventional seven-color spectrometer. Fluxes (C0) with wavelengths from 400 to 750 nm from four emission points are collimated and incident on each spectrometer, respectively.
The spectral characteristics of the nine-color spectrometer were evaluated experimentally and the evaluation results are shown in Figure 6. Note that Figure 6a shows the same results as Figure 5a, i.e. at wavelengths of 4 C0 400–750 nm, all 36 images are detected (4 groups C1–C9). On the contrary, as shown in Fig. 6b–j, when each C0 has a specific wavelength of 530, 550, 570, 590, 610, 630, 650, 670, or 690 nm, there are almost only four corresponding images (four groups detected C1, C2, C3, C4, C5, C6, C7, C8 or C9). However, some of the images adjacent to the four corresponding images are very weakly detected because the C1–C9 transmission spectra shown in Fig. 4b overlap slightly and each C0 has a 10 nm band at a specific wavelength as described in the method. These results are consistent with the C1-C9 transmission spectra shown in Figs. 4b and supplemental videos 2 and 3. In other words, the nine color spectrometer works as expected based on the results shown in fig. 4b. Therefore, it is concluded that the image intensity distribution C1-C9 is the spectrum of each C0.
Spectral characteristics of a nine-color spectrometer. The new nine-color spectrometer generates four sets of nine-color separated images (C1-C9) when the incident light (four C0) has a wavelength of (a) 400-750 nm (as shown in Figure 5a), (b) 530 nm. nm, (c) 550 nm, (d) 570 nm, (e) 590 nm, (f) 610 nm, (g) 630 nm, (h) 650 nm, (i) 670 nm, (j) 690 nm, respectively.
The developed nine-color spectrometer was used for four-capillary electrophoresis (for details, see Supplementary Materials)31,34,35. The four-capillary matrix consists of four capillaries (outer diameter 360 μm and inner diameter 50 μm) located at 1 mm intervals at the laser irradiation site. Samples containing DNA fragments labeled with 8 dyes, namely FL-6C (dye 1), JOE-6C (dye 2), dR6G (dye 3), TMR-6C (dye 4), CXR-6C (dye 5), TOM-6C (dye 6), LIZ (dye 7), and WEN (dye 8) in ascending order of fluorescent wavelength, separated in each of four capillaries (hereinafter referred to as Cap1, Cap2, Cap3, and Cap4). Laser-induced fluorescence from Cap1-Cap4 was collimated with an array of four lenses and simultaneously recorded with a nine-color spectrometer. The intensity dynamics of nine-color (C1-C9) fluorescence during electrophoresis, that is, a nine-color electrophoregram of each capillary, is shown in Fig. 7a. An equivalent nine-color electrophoregram is obtained in Cap1-Cap4. As indicated by the Cap1 arrows in Figure 7a, the eight peaks on each nine-color electrophoregram show one fluorescence emission from Dye1-Dye8, respectively.
Simultaneous quantification of eight dyes using a nine-color four-capillary electrophoresis spectrometer. (a) Nine-color (C1-C9) electrophoregram of each capillary. The eight peaks indicated by arrows Cap1 show individual fluorescence emissions of eight dyes (Dye1-Dye8). The colors of the arrows correspond to the colors (b) and (c). (b) Fluorescence spectra of eight dyes (Dye1-Dye8) per capillary. c Electropherograms of eight dyes (Dye1-Dye8) per capillary. The peaks of Dye7-labeled DNA fragments are indicated by arrows, and their Cap4 base lengths are indicated.
The intensity distributions of C1–C9 on eight peaks are shown in Figs. 7b, respectively. Because both C1-C9 and Dye1-Dye8 are in wavelength order, the eight distributions in Fig. 7b show the fluorescence spectra of Dye1-Dye8 sequentially from left to right. In this study, Dye1, Dye2, Dye3, Dye4, Dye5, Dye6, Dye7, and Dye8 appear in magenta, violet, blue, cyan, green, yellow, orange, and red, respectively. Note that the colors of the arrows in Fig. 7a correspond to the dye colors in Fig. 7b. The C1-C9 fluorescence intensities for each spectrum in Figure 7b were normalized so that their sum equals one. Eight equivalent fluorescence spectra were obtained from Cap1-Cap4. One can clearly observe the spectral overlap of fluorescence between dye 1-dye 8.
As shown in Figure 7c, for each capillary, the nine-color electrophoregram in Figure 7a was converted to an eight-dye electropherogram by multi-component analysis based on the eight fluorescence spectra in Figure 7b (see Supplementary Materials for details). Since the spectral overlap of fluorescence in Figure 7a is not displayed in Figure 7c, Dye1-Dye8 can be identified and quantified individually at each time point, even if different amounts of Dye1-Dye8 fluoresce at the same time. This cannot be done with traditional seven-color detection31, but can be achieved with the developed nine-color detection. As shown by the arrows Cap1 in Fig. 7c, only the fluorescent emission singlets Dye3 (blue), Dye8 (red), Dye5 (green), Dye4 (cyan), Dye2 (purple), Dye1 (magenta), and Dye6 (Yellow) are observed in the expected chronological order. For the fluorescent emission of dye 7 (orange), in addition to the single peak indicated by the orange arrow, several other single peaks were observed. This result is due to the fact that the samples contained size standards, Dye7 labeled DNA fragments with different base lengths. As shown in Figure 7c, for Cap4 these base lengths are 20, 40, 60, 80, 100, 114, 120, 140, 160, 180, 200, 214 and 220 base lengths.
The main features of the nine-color spectrometer, developed using a matrix of two-layer dichroic mirrors, are small size and simple design. Since the array of decachromatic mirrors inside the adapter shown in fig. 3c mounted directly on the image sensor board (see Fig. S1 and S2), the nine-color spectrometer has the same dimensions as the adapter, i.e. 54 × 58 × 8.5 mm. (thickness) . This ultra-small size is two to three orders of magnitude smaller than conventional spectrometers that use gratings or prisms. In addition, since the nine-color spectrometer is configured such that light strikes the surface of the image sensor perpendicularly, space can be easily allocated for the nine-color spectrometer in systems such as microscopes, flow cytometers, or analyzers. Capillary grating electrophoresis analyzer for even greater miniaturization of the system. At the same time, the size of ten dichroic mirrors and bandpass filters used in the nine-color spectrometer is only 10×1.9×0.5 mm or 15×1.9×0.5 mm. Thus, more than 100 such small dichroic mirrors and bandpass filters, respectively, can be cut from a dichroic mirror and a 60 mm2 bandpass filter, respectively. Therefore, an array of decachromatic mirrors can be manufactured at a low cost.
Another feature of the nine-color spectrometer is its excellent spectral characteristics. In particular, it allows the acquisition of spectral images of snapshots, that is, the simultaneous acquisition of images with spectral information. For each image, a continuous spectrum was obtained with a wavelength range from 520 to 700 nm and a resolution of 20 nm. In other words, nine color intensities of light are detected for each image, i.e. nine 20 nm bands equally dividing the wavelength range from 520 to 700 nm. By changing the spectral characteristics of the dichroic mirror and the bandpass filter, the wavelength range of the nine bands and the width of each band can be adjusted. Nine color detection can be used not only for fluorescence measurements with spectral imaging (as described in this report), but also for many other common applications using spectral imaging. Although hyperspectral imaging can detect hundreds of colors, it has been found that even with a significant reduction in the number of detectable colors, multiple objects in the field of view can be identified with sufficient accuracy for many applications38,39,40. Because spatial resolution, spectral resolution, and temporal resolution have a tradeoff in spectral imaging, reducing the number of colors can improve spatial resolution and temporal resolution. It can also use simple spectrometers like the one developed in this study and further reduce the amount of computation.
In this study, eight dyes were quantified simultaneously by spectral separation of their overlapping fluorescence spectra based on the detection of nine colors. Up to nine dyes can be quantified simultaneously, coexisting in time and space. A special advantage of the nine-color spectrometer is its high luminous flux and large aperture (1 × 7 mm). The decane mirror array has a maximum transmission of 92% of the light from the aperture in each of the nine wavelength ranges. The efficiency of using incident light in the wavelength range from 520 to 700 nm is almost 100%. In such a wide range of wavelengths, no diffraction grating can provide such a high efficiency of use. Even if the diffraction efficiency of a diffraction grating exceeds 90% at a certain wavelength, as the difference between that wavelength and a particular wavelength increases, the diffraction efficiency at another wavelength decreases41. The aperture width perpendicular to the direction of the plane in Fig. 2c can be extended from 7 mm to the width of the image sensor, such as in the case of the image sensor used in this study, by slightly modifying the decamer array.
The nine-color spectrometer can be used not only for capillary electrophoresis, as shown in this study, but also for various other purposes. For example, as shown in the figure below, a nine-color spectrometer can be applied to a fluorescence microscope. The plane of the sample is displayed on the image sensor of the nine-color spectrometer through a 10x objective. The optical distance between the objective lens and the image sensor is 200 mm, while the optical distance between the incident surface of the nine-color spectrometer and the image sensor is only 12 mm. Therefore, the image was cut to approximately the size of the aperture (1 × 7 mm) in the plane of incidence and divided into nine color images. That is, a spectral image of a nine-color snapshot can be taken on a 0.1×0.7 mm area in the sample plane. In addition, it is possible to obtain a nine-color spectral image of a larger area on the sample plane by scanning the sample relative to the objective in the horizontal direction in Fig. 2c.
The decachromatic mirror array components, namely M1-M9 and BP, were custom-made by Asahi Spectra Co., Ltd. using standard precipitation methods. Multilayer dielectric materials were applied individually onto ten quartz plates 60 × 60 mm in size and 0.5 mm thick, meeting the following requirements: M1: IA = 45°, R ≥ 90% at 520–590 nm, Tave ≥ 90% at 610–610 nm. 700 nm, M2: IA = 45°, R ≥ 90% at 520–530 nm, Tave ≥ 90% at 550–600 nm, M3: IA = 45°, R ≥ 90% at 540–550 nm, Tave ≥ 90 % at 570–600 nm, M4: IA = 45°, R ≥ 90% at 560–570 nm, Tave ≥ 90% at 590–600 nm, M5: IA = 45°, R ≥ 98% at 580–600 nm , R ≥ 98% at 680–700 nm, M6: IA = 45°, Tave ≥ 90% at 600–610 nm, R ≥ 90% at 630–700 nm, M7: IA = 45°, R ≥ 90% at 620–630 nm, Taw ≥ 90% at 650–700 nm, M8: IA = 45°, R ≥ 90% at 640–650 nm, Taw ≥ 90% at 670–700 nm, M9: IA = 45°, R ≥ 90% at 650-670 nm, Tave ≥ 90% at 690-700 nm, BP: IA = 0°, T ≤ 0.01% at 505 nm, Tave ≥ 95% at 530-690 nm at 530 nm T ≥ 90% at -690 nm and T ≤ 1% at 725-750 nm, where IA, T, Tave, and R are the angle of incidence, transmittance, average transmittance, and unpolarized light reflectance.
White light (C0) with a wavelength range of 400–750 nm emitted by an LED light source (AS 3000, AS ONE CORPORATION) was collimated and incident vertically on the DP of an array of dichroic mirrors. The white light spectrum of LEDs is shown in Supplementary Figure S3. Place an acrylic tank (dimensions 150 × 150 × 30 mm) directly in front of the decamera mirror array, opposite the PSU. The smoke generated when dry ice was immersed in water was then poured into an acrylic tank to observe the nine-color C1-C9 split streams emanating from the array of decachromatic mirrors.
Alternatively, the collimated white light (C0) is passed through a filter before entering the DP. The filters were originally neutral density filters with an optical density of 0.6. Then use a motorized filter (FW212C, FW212C, Thorlabs). Finally, turn the ND filter back on. The bandwidths of the nine bandpass filters correspond to C9, C8, C7, C6, C5, C4, C3, C2 and C1, respectively. A quartz cell with internal dimensions of 40 (optical length) x 42.5 (height) x 10 mm (width) was placed in front of an array of decochromatic mirrors, opposite the BP. The smoke is then fed through a tube into the quartz cell to maintain the concentration of smoke in the quartz cell to visualize the nine-color C1-C9 split streams emanating from the decachromatic mirror array.
A video of the nine-color split light stream emanating from an array of decanic mirrors was captured in time-lapse mode on the iPhone XS. Capture images of the scene at 1 fps and compile the images to create video at 30 fps (for optional video 1) or 24 fps (for optional videos 2 and 3).
Place a 50 µm thick stainless steel plate (with four 50 µm diameter holes at 1 mm intervals) on the diffusion plate. Light with a wavelength of 400-750 nm is irradiated onto the diffuser plate, obtained by passing light from a halogen lamp through a short transmission filter with a cutoff wavelength of 700 nm. The light spectrum is shown in Supplementary Figure S4. Alternatively, the light also passes through one of the 10 nm bandpass filters centered at 530, 550, 570, 590, 610, 630, 650, 670 and 690 nm and hits the diffuser plate. As a result, four radiation points with a diameter of φ50 μm and different wavelengths were formed on a stainless steel plate opposite the diffuser plate.
A four-capillary array with four lenses is mounted on a nine-color spectrometer as shown in Figures 1 and 2. C1 and C2. The four capillaries and four lenses were the same as in previous studies31,34. A laser beam with a wavelength of 505 nm and a power of 15 mW is irradiated simultaneously and evenly from the side to the emission points of four capillaries. The fluorescence emitted by each emission point is collimated by the corresponding lens and separated into nine color streams by an array of decachromatic mirrors. The resulting 36 streams were then directly injected into a CMOS image sensor (C11440–52U, Hamamatsu Photonics K·K.), and their images were simultaneously recorded.
ABI PRISM® BigDye® Primer Cycle Sequencing Ready Reaction Kit (Applied Biosystems), 4 µl GeneScan™ 600 LIZ™ dye was mixed for each capillary by mixing 1 µl PowerPlex® 6C Matrix Standard (Promega Corporation), 1 µl mix size standard. v2.0 (Thermo Fisher Scientific) and 14 µl of water. The PowerPlex® 6C Matrix Standard consists of six DNA fragments labeled with six dyes: FL-6C, JOE-6C, TMR-6C, CXR-6C, TOM-6C, and WEN, in order of maximum wavelength. The base lengths of these DNA fragments are not disclosed, but the base length sequence of DNA fragments labeled with WEN, CXR-6C, TMR-6C, JOE-6C, FL-6C and TOM-6C is known. The mixture in the ABI PRISM® BigDye® Primer Cycle Sequencing Ready Reaction Kit contains a DNA fragment labeled with dR6G dye. The lengths of the bases of the DNA fragments are also not disclosed. GeneScan™ 600 LIZ™ Dye Size Standard v2.0 includes 36 LIZ-labeled DNA fragments. The base lengths of these DNA fragments are 20, 40, 60, 80, 100, 114, 120, 140, 160, 180, 200, 214, 220, 240, 250, 260, 280, 300, 314, 320, 340, 360, 380, 400, 414, 420, 440, 460, 480, 500, 514, 520, 540, 560, 580 and 600 base. The samples were denatured at 94°C for 3 minutes, then cooled on ice for 5 minutes. Samples were injected into each capillary at 26 V/cm for 9 s and separated in each capillary filled with a POP-7™ polymer solution (Thermo Fisher Scientific) with an effective length of 36 cm and a voltage of 181 V/cm and an angle of 60°. FROM.
All data obtained or analyzed in the course of this study is included in this published article and its additional information. Other data relevant to this study are available from the respective authors upon reasonable request.
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Post time: Jan-10-2023