Kohler illumination system and microscopic illumination equipment

Abstract

According to the Kohler illumination system and the microscopic illumination equipment provided by the embodiment of the invention, the ratio of the illumination numerical aperture to the imaging numerical aperture of the Kohler illumination system is 1: 2-1: 4, and the Kohler illumination system comprises a light source, a first lens, a field diaphragm, a reflector, an aperture diaphragm and a condenser which are sequentially arranged along the light path direction; wherein the field diaphragm is arranged on a rear focus of the first lens; the aperture diaphragm is arranged on the front focus of the collecting lens; the distance between the light source and the first lens is greater than the focal length of the first lens; the light source and the aperture diaphragm form a pair of conjugate relation through the first lens; a first distance between the field diaphragm and the collecting lens is 2-4 times of the focal length of the collecting lens; the first distance is the total distance between the field diaphragm and the condenser in the light path direction. The system can be widely applied to the technical field of optical illumination systems.

Description

Technical Field

[0001] This application relates to the field of optical lighting systems, and in particular to a Kohler lighting system and a microscopic lighting device. Background Technology

[0002] Existing microscopic illumination systems typically employ two lenses to form a 4F conjugate system between the light source and the aperture stop, imaging the light source onto the aperture stop and magnifying it. Adjusting the size of the aperture stop can change the illumination numerical aperture (NA) and brightness. Alternatively, a single lens and a condenser lens can form a 4F conjugate system between the field stop and the illumination imaging surface, imaging the field stop onto the illumination imaging surface and reducing the size of the field stop.

[0003] This type of microscopic illumination system can provide a large numerical aperture and relatively uniform illumination, making it suitable for a wide range of applications. However, such systems require a large number of components and have relatively long optical paths, with some systems having optical paths as long as 550 mm, making them difficult to integrate into smaller, more systematic devices. Summary of the Invention

[0004] The purpose of this application is to at least partially solve one of the technical problems existing in the prior art.

[0005] Therefore, one objective of this application is to provide a Kohler lighting system and a microscopic lighting device that reduces design costs and increases integration.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted in the embodiments of this application includes: a Kohler illumination system, comprising: the ratio of the illumination numerical aperture to the imaging numerical aperture of the Kohler illumination system is 1:2-1:4, the system comprising:

[0007] The light source, first lens, field stop, reflector, aperture stop, and condenser are arranged sequentially along the optical path.

[0008] The field stop is located at the rear focal point of the first lens; the aperture stop is located at the front focal point of the condenser lens; and the distance between the light source and the first lens is greater than the focal length of the first lens.

[0009] In addition, a Kohler lighting system according to the above embodiments of this application may also have the following additional technical features:

[0010] Furthermore, in this embodiment of the application, the first distance between the field stop and the condenser lens is 2-4 times the focal length of the condenser lens; the first distance is the total distance between the field stop and the condenser lens along the optical path direction.

[0011] Furthermore, in this embodiment of the application, the condenser lens includes 1 to 3 convex lenses.

[0012] Furthermore, in this embodiment of the application, the illumination numerical aperture of the system is 0.05-0.3.

[0013] Furthermore, in this embodiment, the light source and the aperture stop form a conjugate relationship through the first lens.

[0014] Furthermore, in this embodiment of the application, the field stop and the illumination imaging surface form a conjugate relationship through the condenser lens.

[0015] Furthermore, in this embodiment of the application, the distance between the illumination imaging surface and the condenser lens is greater than the focal length of the condenser lens.

[0016] Furthermore, in this embodiment of the application, the total optical path length of the Kohler lighting system is 200-500mm.

[0017] Furthermore, in this embodiment of the application, the first lens is a convex lens.

[0018] On the other hand, embodiments of this application also provide a microscopic illumination device, which includes the Kohler illumination system as described in any of the preceding claims.

[0019] The advantages and beneficial effects of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application:

[0020] The Kohler lighting system of this application comprises a light source, a first lens, a field stop, a reflector, an aperture stop, and a condenser lens arranged sequentially along the optical path. The field stop is positioned at the rear focal point of the first lens, and the aperture stop is positioned at the front focal point of the condenser lens. The distance between the light source and the first lens is greater than the focal length of the first lens. This system eliminates the need for any lenses between the field stop and the aperture stop, thereby reducing the optical path length and improving system integration. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of a Kohler lighting system provided in one embodiment of this application;

[0023] Figure 2 This is a schematic diagram of the structure of a lighting system in the prior art of this application;

[0024] Figure 3 A schematic diagram of the structure of a Kohler lighting system provided for another embodiment of this application. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] See Figure 1 As shown, one embodiment of this application discloses a Kohler lighting system, wherein the ratio of the lighting numerical aperture to the imaging numerical aperture of the Kohler lighting system is 1:2 to 1:4.

[0027] Specifically, the Kohler lighting system includes a light source 101, a first lens 102, a field stop 103, a reflector 104, an aperture stop 105, and a condenser lens 106 arranged sequentially along the optical path; wherein, the field stop 103 is located at the rear focal point of the first lens 102; the aperture stop 105 is located at the front focal point of the condenser lens 106; the distance between the light source 101 and the first lens 102 is greater than the focal length of the first lens 102.

[0028] Furthermore, in this embodiment, the first distance between the field stop 103 and the condenser lens is 2-4 times the focal length of the condenser lens 106; the first distance is the total distance between the field stop 103 and the condenser lens 106 along the optical path direction.

[0029] Furthermore, in the embodiments of this application, the condenser lens 106 may include one to three convex lenses.

[0030] In a conventional solution, the number of condenser lenses is four. However, in the embodiment described above, the number of convex lenses in condenser lens 106 is one to three. Therefore, compared to conventional solutions, this embodiment reduces the number of convex lenses, which helps to shorten the optical path and thus facilitates the integration of the lighting system into smaller devices.

[0031] Furthermore, in this embodiment of the application, the illumination numerical aperture of the system is 0.05-0.3.

[0032] Furthermore, in this embodiment, the light source 101 and the aperture stop 105 form a conjugate relationship through the first lens 102.

[0033] Furthermore, in this embodiment, the field stop 103 and the illumination imaging surface form a conjugate relationship through the condenser lens 106.

[0034] Furthermore, in this embodiment of the application, the distance between the illumination imaging surface and the condenser lens 106 is greater than the focal length of the condenser lens 106.

[0035] Furthermore, in the embodiments of this application, the total optical path length of the Kohler lighting system is 200-500mm.

[0036] Furthermore, in this embodiment, the first lens 102 is a convex lens.

[0037] Furthermore, the specific structure of this application will be described in conjunction with the accompanying drawings:

[0038] Reference Figure 2 Existing microscopic illumination systems mostly employ the infinity conjugate Kohler illumination method. The light source 201 and the aperture stop 206 form a 4F conjugate system using lenses 202 and 204, which images the light source 201 onto the aperture stop 206 and magnifies the light source 201. Adjusting the size of the aperture stop 206 can change the illumination numerical aperture NA and brightness. The field stop 203 and the illumination imaging surface form a 4F conjugate system using lenses 202 and condenser lens 207, which images the field stop 203 onto the illumination imaging surface and reduces the size of the field stop 203. Adjusting the size of the field stop 203 can change the illumination range.

[0039] In the existing system, lenses 202, 204, and condenser lens 207 are all convex lenses with positive focal lengths. The light source 201 is located at the front focal point of lens 202. The field stop 203 is located at the rear focal point of lens 202, which is also the front focal point of lens 204. The distance between lenses 202 and 204 is the sum of the focal lengths of the two lenses. After passing through lenses 202 and 204, the light source 201 is imaged at aperture stop 206. Aperture stop 206 is located at the rear focal point of lens 204, which is also the front focal point of condenser lens 207. The distance between lenses 204 and condenser lens 207 is the sum of the focal lengths of the two lenses. After passing through lenses 204 and condenser lens 207, the field stop 203 is imaged at the illumination imaging surface, which is located at the rear focal point of condenser lens 207. However, this design uses an infinitely conjugate 4F system, which has many components and a very long structure (such as NIKON's Ti2 system, where the lighting system is as long as 550mm), making it difficult to integrate into a systematic small device.

[0040] To address the aforementioned technical problems, this embodiment proposes a novel lighting system. (Refer to...) Figure 3The system may include a light source 301, a lens 302, a field stop 303, a mirror 304, an aperture stop 305, and a condenser lens 306. Lens 302 is a convex lens, and the condenser lens 306 is a combination of two convex lenses. The focal length of the front convex lens can be 100mm, and the focal length of the rear convex lens can be 60mm. The light source 301 is positioned in front of lens 302, appropriately forward and away from the front focal point of lens 302. Specifically, the distance between the light source 301 and lens 302 is 1.5 times the focal length of lens 302. The relative position of the field stop 303 and the condenser lens 306 is approximately 2-4 times the focal length of the condenser lens 306, preferably 3 times. The light source 301 is imaged onto the aperture stop 305 through the lens 302, forming a magnified image of the light source 301. The aperture stop 305 is located at the front focal point of the condenser lens 306. The field stop 303 is located at the rear focal point of the lens 302, but far from the front focal point of the condenser lens 306. After passing through the condenser lens 306, the field stop 303 is imaged onto the illumination imaging surface, forming a reduced image of the field stop 303. The illumination imaging surface is located behind the condenser lens 306, appropriately rearward and far from its focal point. This forms a set of finite-distance conjugate Kohler illumination systems. The divergent light emitted by the light source 301 of this system is focused by the lens 302 and then reflected by the mirror 304 under the constraint of the field stop 303, focusing the image onto the surface of the aperture stop 305. The imaging area is larger than the maximum light transmission diameter of the aperture stop 305. After being clipped by the aperture stop 305, the light is then focused onto the illumination imaging surface by the condenser lens 306, forming Kohler illumination. The light transmission diameter of the aperture stop 305 is adjustable, and adjusting the size of the light transmission diameter can change the brightness of the illumination imaging surface. The light transmission diameter of the field stop 303 is also adjustable, and adjusting the size of the light transmission diameter can change the area of ​​the illumination imaging surface.

[0041] contrast Figure 2 The common infinity-conjugate Kohler illumination system, in this embodiment, uses a structure that reduces one lens 2, effectively shortening the overall system length. A lens 302 forms a conjugate relationship between the light source 301 and the aperture stop 305, imaging the light source 301 onto the aperture stop 305 and magnifying it. Adjusting the size of the aperture stop 305 can appropriately change the illumination numerical aperture (NA) value. A condenser lens forms a conjugate relationship between the field stop 303 and the illumination imaging surface, imaging the field stop 303 onto the illumination imaging surface and reducing its size. Adjusting the size of the field stop 303 can change the illumination range.

[0042] also, Figure 2The condenser lens of a typical infinity-conjugate Kohler illumination system consists of four lenses: two concave lenses and two convex lenses. In contrast, the condenser lens in this embodiment consists of only two convex lenses. This structure is suitable for imaging concave faces of cells while reducing size and cost.

[0043] This embodiment designs the illumination system by reducing the numerical aperture (NA) of the illumination. Based on the radius of curvature of the concave meniscus, the refractive index of the culture medium, and the imaging position, the tilt angle of the principal ray of the illumination light is calculated. Using this angle and the selected objective lens's NA value, the ratio of the illumination NA to the imaging NA can be derived. Theoretical derivation shows that a ratio of 1:2 to 1:3 is suitable, with 1:3 being the most appropriate.

[0044] In addition, embodiments of this application also provide a microscopic illumination device, which may include the Kohler illumination system as described in any of the preceding claims.

[0045] In summary, the proposed solution has the following advantages:

[0046] 1. In this application, when the ratio of illumination numerical aperture to imaging numerical aperture is 1:3, the edge shadow phenomenon can be reduced well. At the same time, the small illumination numerical aperture NA is also beneficial to the design of the illumination system.

[0047] 2. Based on the theoretical values ​​of the first characteristic, this application designs an illumination system suitable for bottom-of-aperture imaging. The numerical aperture (NA) of this system is 0.15. Furthermore, this system can eliminate one lens, allowing the light source, aperture stop, and illumination imaging surface to be offset from the focal point. This achieves imaging while simplifying the structure and reducing the size. The total optical path length of this application's system is 275 mm, which is half the size of the existing NIKON Ti2 system. This system can also be integrated into a cell imaging analysis system.

[0048] 3. This application utilizes a condenser lens composed of two convex lenses, which effectively shortens the focal length of the condenser lens. This system can both reduce the overall size of the system and increase the numerical aperture (NA) of the illumination.

[0049] 4. This application allows the field stop to be set at a position far from the front focal point of the condenser. After passing through the condenser, the field stop is imaged below the rear focal point of the condenser, forming an illumination imaging surface. In this way, the distance between the illumination imaging surface and the condenser is greater than the focal length of the condenser, which effectively expands the working distance of the condenser. This is very beneficial for placing well plates and culture dishes of various sizes under the condenser, making it convenient for various operations and tests.

[0050] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0051] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0053] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0054] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

Claims

1. A Kohler lighting system, characterized in that, The ratio of the illumination numerical aperture to the imaging numerical aperture of the Kohler illumination system is 1:2 to 1:4, and the system includes: The light source, first lens, field stop, reflector, aperture stop, and condenser are arranged sequentially along the optical path. Wherein, the field stop is disposed at the rear focal point of the first lens; the aperture stop is disposed at the front focal point of the condenser lens; the distance between the light source and the first lens is greater than the focal length of the first lens; The light source and the aperture stop form a conjugate relationship through the first lens; The first distance between the field stop and the condenser lens is 2-4 times the focal length of the condenser lens; the first distance is the total distance between the field stop and the condenser lens along the optical path.

2. The Kohler lighting system according to claim 1, characterized in that, The condenser lens includes 1-3 convex lenses.

3. The Kohler lighting system according to claim 1, characterized in that, The illumination numerical aperture of the system is 0.05-0.

3.

4. The Kohler lighting system according to claim 1, characterized in that, The field stop and the illumination imaging surface form a conjugate relationship through the condenser lens.

5. The Kohler lighting system according to claim 4, characterized in that, The distance between the illumination imaging surface and the condenser lens is greater than the focal length of the condenser lens.

6. The Kohler lighting system according to claim 1, characterized in that, The total optical path length of the Kohler lighting system is 200-500 mm.

7. The Kohler lighting system according to claim 1, characterized in that, The first lens is a convex lens.

8. A microscopic illumination device, characterized in that, The microscopic illumination device includes the Kohler illumination system as described in any one of claims 1 to 7.

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