A Poisson spot microscope

Abstract

The present invention discloses a Poisson spot microscope, which comprises: a Poisson spot generating device, an imaging lens and a detector; the Poisson spot generating device is used to generate a Poisson spot and irradiate it onto a sample to be measured; the imaging lens and the detector are arranged on the reflected light path of the sample to be measured. The present invention uses the Poisson spot as a light source, utilizes the wave nature of light to illuminate the internal measured area of ​​the sample, and greatly reduces the light energy distributed on the propagation path of light, thereby achieving excellent vertical resolution.

Description

Technical Field

[0001] The invention relates to the technical field of microscopes, and in particular to a Poisson spot microscope. Background Art

[0002] Microscopes are devices mainly used to magnify tiny objects so that they can be seen by humans. In modern biomedical research, in order to microscopically examine the internal microstructure of cells or biological tissues, a series of low-irradiance, high-positioning and certain penetrating microscopic techniques have been developed, such as fluorescence microscopy and laser scanning confocal microscopy. Traditional microscopes use geometric optical devices to change the propagation path of light to achieve the effect of illuminating samples and microscopic detection. When performing microscopic detection on samples with a certain degree of transparency and fine structure, such as biological tissues, the traditional light beam is injected through the surface of the sample, illuminates the measured area, and then reflects into the detector. The light beam contains more information about the non-measured area. How to reduce the interference of the light beam in the non-measured area has become a consensus in the research of new microscopic technology. Summary of the invention

[0003] The purpose of the present invention is to provide a Poisson spot microscope to reduce the interference of out-of-focus light during microscopic imaging.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A Poisson spot microscope, comprising:

[0006] Poisson spot generating device, imaging lens and detector;

[0007] The Poisson spot generating device is used to generate a Poisson spot and irradiate it onto the sample to be tested;

[0008] The imaging lens and the detector are arranged on the reflected light path of the sample to be measured; the reflected light formed by the sample to be measured under the irradiation of the Poisson light spot is focused by the imaging lens and then incident on the detector for imaging.

[0009] Optionally, the Poisson spot generating device includes a laser light source, a beam shaper and a light shield;

[0010] The beam shaper and the light shielding plate are sequentially arranged on the outgoing light path of the laser light source along the outgoing direction of the laser light source;

[0011] The laser beam emitted by the laser light source is shaped by the beam shaper to form a circular ring beam; the circular ring beam is diffracted on the light shielding plate to form a Poisson spot.

[0012] Optionally, the Poisson spot generating device further includes a focusing lens, which is disposed between the beam shaper and the shading plate, and is used to amplify the annular light beam so that an inner ring of the annular light beam coincides with an outer edge of the shading plate.

[0013] Optionally, the Poisson spot generating device further includes a light-transmitting pinhole, and the light-transmitting pinhole is arranged between the laser light source and the beam shaper.

[0014] Optionally, the detector is mounted on the backlight surface of the sunshade.

[0015] Optionally, the Poisson spot generating device further comprises a light-transmitting window; the light-transmitting window is arranged between the light-shielding plate and the sample to be measured;

[0016] The inner diameter of the light-transmitting window is smaller than the diameter of the light-shielding plate, and the light-transmitting window is used to shield the diffracted light outside the projection of the light-shielding plate.

[0017] Optionally, the microscope further comprises an imaging pinhole, wherein the imaging pinhole is arranged at a focus of the imaging lens between the imaging lens and the detector.

[0018] Optionally, the detector is a CCD array and / or a spectral analysis device.

[0019] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0020] The present invention discloses a Poisson spot microscope, which comprises: a Poisson spot generating device, an imaging lens and a detector; the Poisson spot generating device is used to generate a Poisson spot and irradiate it onto a sample to be measured; the imaging lens and the detector are arranged on the reflected light path of the sample to be measured. The present invention uses the Poisson spot as a light source, utilizes the wave nature of light to illuminate the internal measured area of ​​the sample, and greatly reduces the light energy distributed on the propagation path of light, thereby achieving excellent vertical resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0022] Figure 1 A schematic diagram of the Poisson spot generation principle provided by the present invention;

[0023] Figure 2A structural diagram of a Poisson spot microscope provided by the present invention;

[0024] Figure 3 A comparison diagram of the geometric optical focusing and Poisson spot focusing effects provided by the present invention; wherein Figure 3 (a) is the geometric optical focusing effect diagram, Figure 3 (b) is the Poisson spot focusing effect diagram;

[0025] Among them, 1 is the laser light source; 2 is the light-transmitting pinhole; 3 is the beam shaper; 4 is the focusing lens; 5 is the light shielding plate; 6 is the detector; 7 is the light-transmitting window; 8 is the imaging lens; 9 is the Poisson spot; 10 is the sample to be measured; and 11 is the imaging pinhole. DETAILED DESCRIPTION

[0026] The purpose of the present invention is to provide a Poisson spot microscope to reduce the interference of out-of-focus light during microscopic imaging.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Poisson spot, also known as Arago spot, is an optical phenomenon caused by the diffraction of light. When monochromatic light is irradiated on a circular obstruction of a certain size, annular concentric diffraction fringes will appear on the light screen, and a tiny bright spot will appear at the center of all the concentric circles. This bright spot is called Poisson spot. Figure 1 shown.

[0029] like Figure 2 As shown, the present invention provides a Poisson spot microscope, which comprises: a Poisson spot generating device, an imaging lens 8, an imaging pinhole 11, a detector 6 and a light-transmitting window 7;

[0030] The Poisson spot generating device is used to generate a Poisson spot 9 and irradiate it onto the sample to be tested; the Poisson spot generating device comprises a laser light source 1, a light pinhole 2, a beam shaper 3, a focusing lens 4 and a light shielding plate 5. In order to improve the efficiency of the light source, the laser light source 1 is transformed into coherent monochromatic light by the light pinhole 2, and then shaped into a ring beam by the beam shaper 3. After the ring beam is magnified by the focusing lens 4, the ring beam is matched with the light shielding plate 5. The ring beam is irradiated at the edge of the light shielding plate 5 to cause light diffraction, and the diffracted light propagates in space to generate Poisson spots and diffraction fringes.

[0031] The present invention further provides a light-transmitting window 7 between the shading plate and the sample to be tested. The light-transmitting window 7 is slightly smaller than the shading plate 5 and is used to shield the diffracted light outside the projection of the shading plate so that the sample is not affected by the interference fringes outside the projection of the shading plate.

[0032] The imaging lens 8 and the detector 6 are arranged on the reflected light path of the sample 10 to be measured; the reflected light formed by the sample 10 to be measured under the irradiation of the Poisson spot is focused by the imaging lens 8 and then incident on the detector 6 for imaging. An imaging pinhole 11 is arranged at the focus of the imaging lens 8 between the imaging lens 8 and the detector 6, and is used to filter out-of-focus plane light beams.

[0033] The detector is installed under the shading plate to receive the light beam emitted by the sample being tested when illuminated by the light spot. Depending on the requirements of the magnifying glass, the detector can be a CCD array to receive the plane impact information of the sample magnification. The detector can also be a spectral analysis device to obtain the hyperspectral information of the sample.

[0034] Traditional microscopes use geometric optical devices to change the propagation path of light to achieve the effect of illuminating samples and microscopic detection. Figure 3 As shown in (a); in comparison, the Poisson spot is an optical phenomenon observed under the wave theory of light. The essence of the Poisson spot is the high-energy area produced by the coherent superposition of the energy beam of light during the wave propagation process. This high-energy area is theoretically less than one-quarter of the wavelength of light. This is called coherent construction in optics. Adjacent to the high-energy area is an area where the wave energy of light cancels each other out, which is called coherent destructive construction in optics. The coherent superposition of these light wave theory explanations causes the Poisson spot to have high contrast and sharp edges. The Poisson spot microscope uses the wave nature of light to perform microscopic measurements. The focusing effect of the Poisson spot microscope of the present invention is as follows: Figure 3 As shown in (b), the Poisson spot microscope of the present invention has a vertical high resolution characteristic (vertical convergence of the light beam) that traditional geometric optics does not have.

[0035] according to Figure 3 It can be seen that compared with the focused spot of traditional geometric optics, the Poisson spot has the characteristics of high contrast, sharp edges, and high vertical resolution. In particular, the geometric beam cannot converge vertically, and the Poisson spot has this characteristic. When performing microscopic detection on samples with a certain degree of transparency and fine structure, such as biological tissue, the traditional light beam is injected through the surface of the sample, illuminates the measured area, and then reflects into the detector. The light beam contains more information about the non-measured area. The Poisson spot uses the wave nature of light to illuminate the internal measured area of ​​the sample and greatly reduces the light energy distributed on the light propagation path, achieving excellent vertical resolution. Figure 3 The black area in the sample under test is the illuminated area. Figure 3 It can be seen that Poisson spot focusing has a significant advantage in vertical contrast compared with geometric optical focusing.

[0036] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0037] This article uses specific examples to illustrate the principles and implementation methods of the invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

Claims

1. A Poisson spot microscope, characterized in that: The microscope comprises: Poisson spot generating device, imaging lens and detector; The Poisson spot generating device is used to generate a Poisson spot and irradiate it onto the sample to be tested; The imaging lens and the detector are arranged on the reflected light path of the sample to be measured; the reflected light formed by the sample to be measured under the irradiation of the Poisson light spot is focused by the imaging lens and then incident on the detector for imaging; The Poisson spot generating device comprises a laser light source, a beam shaper and a light shielding plate; The beam shaper and the light shielding plate are sequentially arranged on the outgoing light path of the laser light source along the outgoing direction of the laser light source; The laser beam emitted by the laser light source is shaped by the beam shaper to form a circular beam; the circular beam is diffracted on the light shielding plate to form a Poisson spot; The Poisson spot generating device further comprises a focusing lens, which is arranged between the beam shaper and the light shielding plate, and is used to amplify the annular light beam so that the inner ring of the annular light beam coincides with the outer edge of the light shielding plate; The Poisson spot generating device further comprises a light-transmitting pinhole, wherein the light-transmitting pinhole is arranged between the laser light source and the beam shaper; The detector is installed on the backlight surface of the shading plate; The Poisson spot generating device further comprises a light-transmitting window; the light-transmitting window is arranged between the light-shielding plate and the sample to be measured; The inner diameter of the light-transmitting window is smaller than the diameter of the light-shielding plate, and the light-transmitting window is used to shield the diffracted light outside the projection of the light-shielding plate; The microscope also includes an imaging pinhole disposed at a focus of the imaging lens between the imaging lens and the detector.

2. The Poisson spot microscope according to claim 1, characterized in that: The detector is a CCD array and / or a spectrum analysis device.

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