SUMMERY OF THE UTILITY MODEL
In view of the above problems, an object of the present invention is to provide an optical system for realizing a light curtain, so as to solve the problems of the existing light curtain imaging system, such as low light source utilization rate, being not suitable for a light source with a larger diffusion angle, etc.
The utility model provides an optical system for realizing a light curtain, which comprises a light source, a light collimation part and a light diffusion part which are arranged in sequence; the light collimation part comprises a first collimating mirror and a second collimating mirror, and the first collimating mirror is arranged between the light source and the second collimating mirror; the first collimating mirror is used for gathering light rays emitted by the light source to the Y-axis direction and collimating the light rays parallel to the Z axis, and the second collimating mirror is used for collimating the light rays gathered to the Y-axis direction and parallel to the Z axis to form flat light beams; the light diffusion part is used for diffusing the flat light beam into the light curtain.
In addition, the optional structure is that the first collimating mirror comprises a first surface and a second surface, the first surface is a plane close to the light source, and the second surface is an anamorphic aspheric surface far away from the light source; the second collimating mirror comprises a third surface and a fourth surface, the third surface is a plane close to the first collimating mirror, and the fourth surface is a deformed aspheric surface far away from the first collimating mirror.
In addition, the optional structure is that the quadric coefficient of the second surface with the X axis as the meridian is different from the quadric coefficient with the Y axis as the meridian; the fourth surface has a different quadric coefficient with the X axis as the meridian from the quadric coefficient with the Y axis as the meridian.
In addition, the optional structure is that the thicknesses of the first collimating mirror and the second collimating mirror in the direction along the Z axis are the same; the Z-axis direction is parallel to the optical axis direction of the first collimating mirror and the second collimating mirror.
In addition, the optical axis directions of the light source, the first collimating mirror and the second collimating mirror are parallel to each other.
Further, an alternative configuration is that the first collimating mirror and the second collimating mirror include a reflecting mirror or a transmitting mirror.
Further, an alternative configuration is that the light source comprises an LED light source or a laser light source.
Further, an alternative structure is such that the light diffusion portion includes a cylindrical mirror or a free-form surface mirror.
In addition, the optional structure is that the device further comprises at least two reflecting mirrors arranged between the first collimating mirror and the second collimating mirror; the at least two reflectors are used for folding the light path of the light between the first collimating mirror and the second collimating mirror.
In addition, an optional structure is that a first reflecting mirror and a second reflecting mirror which are parallel to each other are arranged between the first collimating mirror and the second collimating mirror; the incident light of the first reflector and the emergent light of the second reflector are parallel to each other.
From the above technical solutions, the optical system for realizing a light curtain of the present invention includes a light source, a light collimation portion and a light diffusion portion; the light collimation part comprises a first collimating mirror and a second collimating mirror; the first collimating mirror is used for gathering light rays emitted by the light source to the Y-axis direction and collimating the light rays parallel to the Z axis, and the second collimating mirror is used for collimating the light rays gathered to the Y-axis direction and parallel to the Z axis to form flat light beams; the light diffusion part is used for diffusing the flat light beams into the light curtain, the utilization rate of the light source can be close to 100%, and the light diffusion part is also suitable for light sources with larger diffusion angles, and has the advantages of simple structure, low cost and wide application range.
Detailed Description
To describe in detail the optical system of the present invention for implementing the light curtain, a detailed description will be given below of specific embodiments of the present invention with reference to the accompanying drawings.
Fig. 1 shows a schematic principle of an optical system implementing a light curtain according to an embodiment of the present invention.
As shown in fig. 1, the optical system for realizing a light curtain according to the embodiment of the present invention includes a light source 1, a light collimation part, and a light diffusion part 4; wherein, the light collimation part further comprises a first collimating mirror 2 and a second collimating mirror 3, and the first collimating mirror 2 is arranged between the light source 1 and the second collimating mirror 3; the first collimating mirror 2 is used for gathering light rays emitted by the light source 1 to the Y-axis direction and collimating the light rays parallel to the Z axis, the second collimating mirror 3 is arranged on one side of the first collimating mirror 2, which is far away from the light source 1, and the second collimating mirror 3 is used for collimating the light rays gathered to the Y-axis direction and parallel to the Z axis to form flat light beams; the light diffusion part 4 is used for diffusing the flat light beams into the light curtain, so that the arrangement of a diaphragm can be saved, and the utilization rate of the light source 1 is improved.
In one embodiment of the present invention, the first collimating mirror 2 may include a first surface and a second surface, the first surface being a plane close to the light source 1, the second surface being an anamorphic aspherical surface far from the light source 1; similarly, the second collimating mirror 3 includes a third surface and a fourth surface, the third surface is a plane close to the first collimating mirror 2, and the fourth surface is a deformed aspheric surface far away from the first collimating mirror 2. In other words, first collimating mirror 2 and second collimating mirror 3 all can adopt the plano-convex mirror, carry out diversified collimation through the light that first collimating mirror 2 and the cooperation of second collimating mirror 3 sent light source 1, and the flat light beam after the collimation finally diverges away through light diffusion portion 4, forms the target light curtain.
The quadric surface coefficient of the second surface taking the X axis as the meridian is different from the quadric surface coefficient taking the Y axis as the meridian; the quadric coefficient of the fourth surface with the X axis as the meridian is different from the quadric coefficient with the Y axis as the meridian, and similarly, the curvature radius and the like of the second surface and the fourth surface can also be set as different parameters.
Further, the thicknesses of the first collimating mirror 2 and the second collimating mirror 3 in the Z-axis direction, which is a direction parallel to the optical axis directions of the first collimating mirror 2 and the second collimating mirror 3, may be set to be the same; it should be noted that the Z-axis direction mainly refers to the emitting direction of the light source 1 in fig. 1, i.e. the optical axis direction of the first collimating mirror 2 or the second collimating mirror 3, the X-axis direction mainly refers to the direction vertical to the Z-axis direction in fig. 1, and the Y-axis direction mainly refers to the direction vertical to the Z-axis and the plane vertical to the drawing in fig. 1.
In order to ensure the accuracy of forming the light curtain and improve the utilization rate of the light source, in the optical system for realizing the light curtain of the present invention, the optical axis directions of the light source 1, the first collimating mirror 2 and the second collimating mirror 3 may be set to be parallel to each other, and the first collimating mirror 2 and the second collimating mirror 3 include a reflecting mirror or a transmitting mirror, which may be specifically set according to an applicable scene or requirement, and is not limited to the specific structure shown in the drawings.
In another embodiment of the present invention, the light source 1 may adopt various types of light sources such as an LED light source or a laser light source; the light diffusion portion 4 can be a structure having a light diffusion function such as a cylindrical mirror or a free-form surface mirror.
In order to ensure the miniaturization of the whole size of the optical system, in the optical system for realizing the light curtain, at least two reflectors can be arranged between the first collimating mirror 2 and the second collimating mirror 3; the at least two reflectors are used for folding the light path of the light between the first collimating mirror 2 and the second collimating mirror 3, so that the effect of reducing the size of the whole optical system is achieved.
In particular, fig. 2 shows a schematic principle of an optical system implementing a light curtain according to another embodiment of the present invention.
As shown in fig. 2, in this embodiment, the directions of the X-axis, the Y-axis and the Z-axis are the same as the coordinates in fig. 1, and the optical system for realizing the light curtain includes a light source 1, a first collimating mirror 2, a first reflecting mirror 5, a second reflecting mirror 6, a second collimating mirror 3 and a light diffusing part 4, which are arranged in this order; the incident light of the first reflector 5 is the light processed by the first collimator lens 2, the reflected light of the second reflector 6 is further collimated by the second collimator lens 3, and the final light is diffused into a light curtain by the light diffusion part 4.
Wherein the first reflecting mirror 5 and the second reflecting mirror 6 may be disposed parallel to each other, and the incident light of the first reflecting mirror 5 and the outgoing light of the second reflecting mirror 6 are parallel to each other.
The optical system implementing the light curtain of the present invention will be explained below with reference to specific examples.
In the present invention, the light source 1 is set to be a point light source having a uniform angle of divergence of 33 °, the first surface of the first collimating mirror is a flat surface, the second surface is an anamorphic aspherical surface, the second surface has a conic coefficient of-0.558 and a radius of curvature of 0.845 with the Y-axis as a meridian (an intersection of a cross section passing through the optical axis and the lens surface), the second conic coefficient of-0.791 and the radius of curvature of 0.624 and a thickness of 0.5mm with the X-axis as a meridian, and the material is BK 7.
Furthermore, the third surface of the second collimating mirror is a plane, the fourth surface is a deformed aspheric surface, the conic coefficient of the second collimating mirror taking the Y axis as the meridian is-0.547, the curvature radius is 1177.75mm, the conic coefficient of the second collimating mirror taking the X axis as the meridian is-0.791, the curvature radius is 0.166mm, the thickness is 0.5mm, and the material is BK 7. The light source focuses light beams to the Y-axis direction through the first collimating mirror, the collimation is parallel to the Z-axis, the light beams focused to the Y-axis direction are collimated through the second collimating mirror, the collimated flat light beams are diffused into a light curtain through the light diffusion part, the fan-shaped angle and the thickness effect of the light curtain can reach the expectation, and meanwhile, the utilization efficiency of the optical system of the utility model to the light source can approach 100% due to the fact that the diaphragm is not used for limiting the light beams.
The specific optical parameters of the light collimating part and the light diffusing part may be adjusted according to the application scene, the size or thickness of the light curtain to be formed, and the like, and are not particularly limited to the above parameters.
The optical system for realizing the light curtain can improve the utilization rate of the light source with a larger diffusion angle, form the light curtain with a very thin thickness, and has the advantages of small overall size, simple structure and low cost.
The optical system proposed according to the utility model to realize the light curtain is described above by way of example with reference to the accompanying drawings. However, it will be appreciated by those skilled in the art that various modifications may be made to the optical system for implementing a light curtain as set forth in the foregoing without departing from the scope of the utility model. Therefore, the scope of the present invention should be determined by the contents of the appended claims.