CN109991731A - Optical path changing device and optical interference system - Google Patents

Abstract

The invention discloses an optical path changing device, comprising a medium body and an optical surface, the medium body includes a pair of surfaces opposite and parallel to each other, and incident light enters the medium body from any surface of the paired surfaces, The transmission direction of the transmitted light is consistent with the transmission direction of the incident light, and the transmitted light is irradiated to the optical surface, the medium body can be rotated to change the incident angle of the incident light entering the medium body, and the optical surface is used to adjust the light propagation direction. The optical path changing device is applied in an optical system to change the optical path, and can overcome the problem that the existing push-broom method for changing the optical path has high requirements for no inclination and a high implementation cost. The invention also discloses an optical interference system.

Description

Optical path changing device and optical interference system

technical field

The present invention relates to the technical field of optical applications, in particular to an optical path changing device. The invention also relates to an optical interference system.

Background technique

In recent years, with the gradual deepening of the application of optical technology in the field of measurement, the applications based on coherent optics are increasing day by day, such as length measurement, vibration measurement, Fourier transform spectroscopy measurement, etc. Measurement techniques using coherent optics theory all need to change the optical path difference of the measurement system by changing the optical path length of part of the optical path, so that the target information can be obtained according to the change of the optical path difference and through subsequent processing methods.

In the prior art, the method used to change the optical path is mainly a push-broom type. For example, in the time-modulated Fourier transform spectral modulation technology, it is necessary to install a reflective surface that moves in translation along a straight line. During the measurement, the object to be measured is moved along a straight line in translation over time to cause the change of the optical path. However, this method of translating the reflective surface along a straight line requires the reflective surface to translate along a straight line without tilt, because if the reflective surface is tilted, the reference light wavefront and the measurement light wavefront will lose the parallel relationship, resulting in an intersection angle, which will cause The fluctuation of the light intensity of the interference signal and the deviation of the sampling from the true value will lead to the deviation of the measurement result. Therefore, this method has high requirements for no inclination, which in turn results in a high implementation cost.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an optical path changing device, which can be used in an optical system to change the optical path, which can overcome the high requirement of no inclination in the existing push-broom method of changing the optical path, which will result in a high realization cost. The problem. The present invention also provides an optical interference system.

To achieve the above object, the present invention provides the following technical solutions:

An optical path changing device includes a medium body and an optical surface, the medium body includes a pair of surfaces opposite to each other and parallel to each other, and incident light enters the medium body from any surface of the pair of surfaces, The other surface of the paired surface transmits, the propagation direction of the transmitted light is consistent with the propagation direction of the incident light, and the transmitted light irradiates the optical surface, the medium body can be rotated so that the incident light enters the incident light of the medium body The angle is changed, and the optical surface is used to adjust the propagation direction of the light.

Preferably, both surfaces of the pair are planar.

Preferably, the medium body includes one or more pairs of surfaces.

Preferably, the shape of the medium body is a symmetrical geometric shape, and the shape of the medium body is a cube, a rectangular parallelepiped or a hexahedral cylinder.

Preferably, the optical surface is a reflective surface, a transmissive surface or a transflective surface.

Preferably, the optical surface is a reflective surface, the light transmitted from the other surface of the pair of surfaces is vertically irradiated to the optical surface, and the optical surface is used to reflect the light back to the medium body to cause the light source road back.

Preferably, it also includes a driving mechanism connected with the medium body for driving the medium body to rotate.

Preferably, the rotation axis of the driving mechanism is parallel to the rotation center axis of the medium body.

Preferably, the spectral band of the optical path changing device covers the ultraviolet light band, the visible light band and the infrared light band.

An optical interference system includes the above-mentioned optical path changing device.

It can be seen from the above technical solutions that the optical path changing device provided by the present invention includes a medium body and an optical surface, the medium body includes a pair of surfaces that are opposite and parallel to each other, and the incident light enters the medium body from any surface of the paired surfaces, Transmitting from the other surface of the paired surfaces, the propagation direction of the transmitted light coincides with the propagation direction of the incident light and the transmitted light is irradiated to the optical surface, which is used to adjust the propagation direction of the light. By rotating the medium body, the incident angle of the incident light entering the medium body can be changed, the propagation path of the light in the medium body can be changed, and the optical path in the medium body can be changed, thereby realizing the change of the optical path. The optical path changing device relies on the machining accuracy and adjustment accuracy of the optical parts such as the optical medium body and the optical surface to ensure the parallelism of the reference light wavefront and the measurement light wavefront. Compared with the push-broom method of changing the optical length, it can overcome the problem that the existing push-broom method of changing the optical length has a high requirement for no inclination and will result in a higher implementation cost.

The optical interference system provided by the present invention can achieve the above beneficial effects.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of an optical path changing device according to an embodiment of the present invention.

Detailed ways

In order to make those skilled in the art better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

An embodiment of the present invention provides an optical path changing device, including a medium body and an optical surface, the medium body includes a pair of surfaces facing each other and parallel to each other, and incident light enters the pair of surfaces from any surface of the pair of surfaces. The dielectric body is transmitted from the other surface of the paired surfaces, the propagation direction of the transmitted light is consistent with the propagation direction of the incident light, and the transmitted light is irradiated on the optical surface, and the dielectric body can be rotated to allow the incident light to enter the optical surface. The incident angle of the medium body is changed, and the optical surface is used to adjust the propagation direction of light.

The medium body is made of a light-transmitting optical medium, and the two pairs of surfaces it includes are opposite and parallel to each other, so that when incident light enters the medium body from any one of the surfaces, the light can be transmitted from the other surface, And the propagation direction of the transmitted light is consistent with the propagation direction of the incident light, so that the propagation direction of the light does not change after passing through the medium body.

The medium body can be rotated, and the rotation of the medium body can change the incident angle of the incident light entering the medium body. The incident angle of the incident light entering the medium body refers to the angle between the incident light and the normal line of the surface of the medium body on which the incident light irradiates. .

By rotating the medium body, the optical path changing device can change the incident angle of the incident light entering the medium body, and can change the propagation path of the light in the medium body and the optical path in the medium body, so as to realize the change of the optical path. The optical path changing device is applied in the optical system, mainly relying on the machining accuracy and adjustment accuracy of the optical parts such as the optical medium body and the optical surface to ensure the parallelism of the reference light wavefront and the measurement light wavefront, and the influence of the vibration of the optical parts on the wavefront intersection angle It is very weak, so compared with the existing push-broom method of changing the optical length, it can overcome the problem that the existing push-broom method of changing the optical length has a high requirement for no inclination, which will result in a higher implementation cost.

The optical path changing device will be described in detail below with reference to the specific embodiments and the accompanying drawings.

The optical path changing device of this embodiment includes a medium body and an optical surface, wherein the medium body includes a pair of surfaces facing each other and parallel to each other.

The two surfaces in the pair on the medium body can be curved surfaces, and the two curved surfaces in the pair need to be opposite and parallel to each other, so that the incident light can enter the medium body from either surface, and the light can be transmitted from the other surface, and The propagation direction of the transmitted light is consistent with the propagation direction of the incident light, and it satisfies the change of the incident angle of the incident light entering the medium body when the medium body rotates, so as to ensure that the propagation path of the light in the medium body changes when the medium body rotates, so that the light in the medium body changes. Optical path changes.

Preferably, the two pairs of surfaces on the medium body can be both planes, and it is required to satisfy the requirement that when incident light enters the medium body from any one of the surfaces, the light can be transmitted from the other surface, and the propagation direction of the transmitted light is the same as that of the incident light. The propagation direction is the same, and the incident angle of the incident light entering the medium body changes when the medium body rotates, so that the propagation path of the light in the medium body changes when the medium body rotates, so that the optical path in the medium body changes.

During specific implementation, the medium body may include one or more pairs of surfaces, which may be set in combination with the shape of the medium body and application requirements. Optionally, the shape of the dielectric body may be a geometric structure with symmetrical parallel surfaces such as a cube, a cuboid, or a hexahedral cylinder, but is not limited to this, and the dielectric body may also be other geometric structures with symmetrical parallel surfaces, which are also described herein. within the scope of protection of the invention.

Please refer to FIG. 1 . FIG. 1 is a schematic diagram of an optical path changing device according to an embodiment of the present invention. In this embodiment, the dielectric body 10 includes two pairs of surfaces. The first pair of surfaces is a surface 101 and a surface 103 . The two pairs of surfaces are surface 102 and surface 104, each of which is flat. Referring to the optical path diagram of light passing through the medium shown in FIG. 1, it can be seen that the incident light enters the medium 10 from the surface 101 of the medium, and the light is transmitted from the surface 103 of the medium. The propagation directions are the same, and the transmitted light is irradiated to the optical surface 11 . The optical path changing device is arranged in the preset optical path of the optical system, and the optical path between the reference plane 13 and the optical plane 11 can be changed by rotating the medium body 10 .

Preferably, the optical path changing device may further include a driving mechanism connected with the medium body for driving the medium body to rotate, and the driving mechanism drives the medium body to rotate during application, so that the optical path of light in the medium body changes. , thereby changing the optical path of the optical system. Referring to FIG. 1 , preferably, the rotating shaft of the driving mechanism 12 can be set to be parallel to the rotation center axis 100 of the medium body 10 , so that the medium body can be better driven to rotate by the driving mechanism. In a specific implementation, the driving mechanism may adopt a transmission belt, a gear or an electromagnetic driving component.

In the optical path changing device, the transmitted light transmitted from the medium body irradiates the optical surface, and the optical surface is used to adjust the propagation direction of the light. The optical surface can be a reflective surface, and it can be set that the light transmitted from the medium body is vertically irradiated to the optical surface, that is, the light transmitted from the other surface of the paired surface of the medium body is vertically irradiated to the optical surface, and the optical surface reflects the light back to the optical surface. The dielectric body makes the light return the same way. The optical surface can also be a transmissive surface or a transflective surface, which can be set according to application requirements in practical applications.

In practical applications, it is necessary to set the distance from the central axis of rotation of the medium body to the optical surface to be greater than the maximum distance from the point on the surface of the medium body to its central axis of rotation, so as to ensure that the medium body will not collide with the optical surface during the rotation process. As shown in FIG. 1 , the cross-section of the dielectric body 10 is square, and the distance H from the central axis of the rotating shaft of the dielectric body 10 to the optical surface 11 is greater than half of the diagonal length D of the cross-section of the dielectric body, that is, H>D/2 is satisfied. , where H is the distance from the central axis of the rotating shaft of the medium body 10 to the optical surface 11 , D is the diagonal length of the cross section of the medium body, which is the maximum distance from the point on the surface of the medium body to the central axis of its rotation.

During specific implementation, the medium body may be made of a light-transmitting material, which is not specifically limited in this embodiment. Preferably, the spectral band of the optical path changing device covers the ultraviolet light band, the visible light band and the infrared light band, and the device can be applied to ultraviolet light, visible light and infrared light.

An embodiment of the present invention further provides an optical interference system, including the above-mentioned optical path changing device.

In the optical interference system provided by the present invention, the optical path changing device used includes a medium body and an optical surface, the medium body includes a pair of surfaces opposite to each other and parallel to each other, and incident light enters the medium body from any surface of the paired surfaces. , transmitted from the other surface of the paired surfaces, the propagation direction of the transmitted light is consistent with the propagation direction of the incident light and the transmitted light is irradiated to the optical surface, which is used to adjust the propagation direction of the light. By rotating the medium body, the incident angle of the incident light entering the medium body can be changed, the propagation distance of the light in the medium body can be changed, and the optical distance in the medium body can be changed, so as to realize the change of the optical distance, which is different from the existing push-broom type. Compared with the optical path method, it can overcome the problem that the existing push-broom method of changing the optical path has a high requirement for no inclination and a higher implementation cost.

The optical path changing device and the optical interference system provided by the present invention have been described in detail above. The principles and implementations of the present invention are described herein by using specific examples, and the descriptions of the above embodiments are only used to help understand the method and the core idea of the present invention. It should be pointed out that for those skilled in the art, without departing from the principle of the present invention, several improvements and modifications can also be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims (10)

1. a kind of light path changes device, which is characterized in that including dielectric and optical surface, both the dielectric includes it is opposite and The pairs of surface being parallel to each other, incident light from any one surface on the pairs of surface enter the dielectric, from it is described in pairs Another surface transmission on surface goes out, the direction of propagation of transmitted light and the direction of propagation of incident light is consistent and transmitted light be irradiated to it is described Optical surface, the dielectric is rotatable and incident light is made to enter the incidence angle change of the dielectric, and the optical surface is for adjusting The direction of propagation of whole light.

2. light path according to claim 1 changes device, which is characterized in that two pairs of surfaces are all plane.

3. light path according to claim 1 changes device, which is characterized in that the dielectric include one group or multiple groups at To surface.

4. light path according to claim 3 changes device, which is characterized in that the shape of the dielectric is symmetrical geometry Shape, the shape of the dielectric are square, cuboid or six face cylinders.

5. light path according to claim 1 changes device, which is characterized in that the optical surface be reflecting surface, transmission plane or Person's half-reflection and half-transmission face.

6. light path according to claim 1 changes device, which is characterized in that the optical surface is reflecting surface, from it is described at The optical surface is arrived to the light vertical irradiation that another surface transmission on surface goes out, the optical surface is used to reflect light back into be given an account of Plastid makes light backtracking.

7. light path according to claim 1-6 changes device, which is characterized in that further include connecting with the dielectric The driving mechanism for driving the dielectric to rotate connect.

8. light path according to claim 7 changes device, which is characterized in that the shaft of the driving mechanism and the medium The Pivot axle of body is parallel.

9. light path according to claim 1-6 changes device, which is characterized in that the light path changes the spectrum of device Section covers ultraviolet light wave band, visible light wave range and infrared band.

10. a kind of optical interference system, which is characterized in that change device including the described in any item light paths of claim 1-9.