WO2019127858A1

WO2019127858A1 - Optical beam splitter and optical device comprising optical beam splitter

Info

Publication number: WO2019127858A1
Application number: PCT/CN2018/075936
Authority: WO
Inventors: 杜春雷; 夏良平
Original assignee: 珠海迈时光电科技有限公司
Priority date: 2017-12-29
Filing date: 2018-02-09
Publication date: 2019-07-04
Also published as: CN109100872A

Abstract

Provided in the present invention is an optical beam splitter, comprising a plurality of optical beam splitting units, each beam splitting unit being composed of a plurality of optical refraction surfaces of different directions, each optical refraction surface satisfying the following relationship: each optical refraction surface refracts parallel incident light in different directions to form a split beam, the angle α of the split beam satisfying the following relationship: Sinθo＝nSinθi, α＝θo-θi, n being the refractive index of the material of the optical refraction surfaces, θ being the angle between the optical refraction surfaces and the perpendicular plane of the incident light, and θo being the angle of refraction of the light ray after passing through the optical refractive surfaces. The split beam angle of the optical beam splitter of the present invention is only related to the angle of inclination and the refractive index of the material of the refractive surfaces, and is not related to the feature size thereof, so that it is easier to implement large angle beam splitting.

Description

Optical beam splitter and optical device comprising the same optical beam splitter

Technical field

The present invention relates to an optical device, and more particularly to an optical beam splitter and an optical device including the same optical beam splitter.

Background technique

Optical beam splitters are one of the most widely used devices in optical applications such as optical communication, optical shaping and optical detection. The beam splitting angle, spot uniformity on the target surface after splitting, and dispersion characteristics are key indicators for determining device performance.

At present, the commonly used optical beam splitter is composed of a diffractive optical structure. The grating is diffracted two-dimensionally by the principle of grating diffraction, and then the pixels are arranged and combined to form a coded phase distribution after passing through the grating diffraction structure. Strong coherence, its encoded phase distribution will produce interference and form a specific spectroscopic result after the beam is transmitted to the far field.

However, the central zero-order intensity of this beam splitting structure is very sensitive to the depth of the grating structure. A slight error in the grating depth will produce a strong zero-order light, resulting in uneven beam splitting. Secondly, its pixelated features The size is closely related to the beam splitting angle. The smaller the pixelized feature size, the larger the beam splitting angle, but the too small feature size is very difficult to process the device. In addition, the diffraction structure is very sensitive to the wavelength of the incident light and is a strong Dispersion structure, the beam splitting angle is very different after incident at different wavelengths.

Therefore, this type of device is greatly limited in application.

Summary of the invention

In view of this, it is necessary to provide an optical beam splitter aimed at solving the application limitations of the optical beam splitter provided in the prior art.

In order to achieve the above object, the present invention adopts the following technical solutions:

In one aspect, the invention provides an optical beam splitter, the optical beam splitter comprising a plurality of optical splitting units, each of the optical splitting units being composed of a plurality of optically refractive surfaces of different directions, each of the optical The refractive surface satisfies the following relationship:

Each of the optical refractive surfaces refracts the incident parallel light to a different direction to form a split beam, and the splitting angle α of the split beam satisfies the following relationship:

Sin θo=n sin θi

α=θo-θi

Where n is the refractive index of the material constituting the optical refractive surface, θi is the angle between the optical refractive surface and the plane perpendicular to the incident light, and θo is the angle of refraction after the light passes through the optical refractive surface. .

In some preferred embodiments, each of the optical refractive surfaces refracts the incident parallel light to a different direction, and the energy of the beam spot on which the split beam is incident on the target surface is equal to the refractive surface of the beam spot. It is proportional to the projected area of the plane perpendicular to the incident light. In some preferred embodiments, the material of the optical beam splitter is an optical plastic or an optical glass.

In some preferred embodiments, the lateral dimension of each of the beam splitting units is less than the incident beam spot size such that the incident beam at least completely covers the beam splitting unit.

In some preferred embodiments, each of said beam splitting units is arranged in a periodic array.

In some preferred embodiments, the beam split by the beam splitter can form a regular beam splitting arrangement on the target surface.

In some preferred embodiments, the beam split by the beam splitter can form a random beam split arrangement on the target surface.

In another aspect, the invention also provides an optical device comprising the optical beam splitter.

The present invention adopts the above technical solutions, and can achieve the following beneficial effects:

The optical beam splitter provided by the present invention comprises a plurality of optical splitting units, each of the optical splitting units being composed of a plurality of optical refractive surfaces of different directions, each of the optical refractive surfaces satisfying the following relationship: The optical refractive surface refracts the incident parallel light to different directions to form a splitting beam, and the splitting angle α satisfies the following relationship:

Sin θo=n sin θi

α=θo-θi

Wherein n is the refractive index of the material constituting the optical refractive surface, θi is the angle between the optical refractive surface and the plane perpendicular to the incident light, and θo is the angle of refraction after the light passes through the optical refractive surface, and the light provided by the present invention The beam splitter, whose beam splitting angle is only related to the tilt angle of the refractive surface and the refractive index of the material, is independent of its feature size, so it is easier to achieve large angle splitting.

In addition, the optical beam splitter according to the present invention, each of the optical refractive surfaces refracts the incident parallel light to a different direction, and the energy of the beam spot on which the split beam is incident on the target surface corresponds to the beam spot. The refractive surface is proportional to the projected area perpendicular to the incident light, such that the splitting energy of the optical beam splitter on the target surface is determined by the angle between the corresponding refractive surface and the plane perpendicular to the incident light, and is no longer subject to The depth of the microstructure is limited, so there is no strong central zero-order light.

In addition, the optical beam splitter provided by the present invention has optical dispersion material which is much smaller than the dispersion characteristic of the diffraction structure due to the use of optical plastic or optical glass material, and the dispersion degree is much lower than that of the diffraction type beam splitter, and the applicable optical band range of the device is more width.

DRAWINGS

1 is a schematic view showing the operation of an optical beam splitter according to Embodiment 1 of the present invention.

Figure 2 is a cross-sectional view showing an optical beam splitter according to Embodiments 1 and 4 of the present invention.

3 is a plan view of each of the optical splitting units in the optical beam splitter according to Embodiment 1 of the present invention.

4 is a plan view of an optical beam splitter according to Embodiment 1 of the present invention.

Figure 5 is a cross-sectional view showing an optical beam splitter according to

Embodiments

2 and 3 of the present invention.

Figure 6 is a plan view of each of the optical splitting units in the optical beam splitter according to Embodiment 2 of the present invention.

Figure 7 is a plan view of an optical beam splitter according to Embodiment 2 of the present invention.

Figure 8 is a plan view of each of the optical splitting units in the optical beam splitter according to Embodiment 3 of the present invention.

Fig. 9 is a plan view showing each of the optical splitting units in the optical beam splitter according to the fourth embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to FIG. 1 , a working principle diagram of an optical beam splitter provided by the present invention, the optical beam splitter 11 includes a plurality of optical splitting units (not shown), and each of the optical splitting units is composed of several different The optical refractive surface of the direction is composed, and each of the optical refractive surfaces satisfies the following relationship:

Each of the optical refractive surfaces refracts the incident parallel light 13 in a different direction to form a split beam 14 whose splitting angle α satisfies the following relationship:

Sin θo=n sin θi

α=θo-θi

Where n is the refractive index of the material constituting the optical refractive surface, θi is the angle between the optical refractive surface and the plane perpendicular to the incident light, and θo is the angle of refraction after the light passes through the optical refractive surface.

It can be understood that the optical beam splitter provided by the present invention is more likely to realize large-angle splitting because its beam splitting angle is only related to the tilt angle of the refractive surface and the refractive index of the material, regardless of its feature size.

In some preferred embodiments, each of the optically refractive surfaces refracts the incident parallel light 13 in a different direction to form an energy level of the beam spot 15 incident on the target surface 12 by the split beam 14 and the beam spot. The corresponding refractive surface of the 15 is proportional to the projected area of the plane perpendicular to the incident light, such that the splitting energy of the optical beam splitter on the target surface 12 is determined by the angle between the corresponding refractive surface and the plane perpendicular to the incident light. It is no longer limited by the depth of the microstructure, so there is no strong central zero-order light.

In some preferred embodiments, the material of the optical beam splitter is an optical plastic or an optical glass.

It can be understood that since the optical beam splitter adopts optical plastic or optical glass material, its dispersion characteristic is much smaller than that of the diffraction structure, and its dispersion degree is much lower than that of the diffraction type beam splitter, and the device has a wider optical band range.

It can be understood that the three-dimensional diffraction unit is not limited to the periodic array arrangement, and may actually be a random arrangement.

Sin θo=n sin θi

α=θo-θi

Where n is the refractive index of the material constituting the optical refractive surface, θi is the angle between the optical refractive surface and the plane perpendicular to the incident light, and θo is the angle of refraction after the light passes through the optical refractive surface, due to the optical beam splitter The beam splitting angle is only related to the angle of inclination of the refractive surface and the refractive index of the material, and is independent of its feature size, so it is easier to achieve large angle splitting.

Further, the present invention provides an optical apparatus comprising the above-described optical beam splitter.

The specific implementation of the present invention is described in detail below in conjunction with specific embodiments:

Example 1:

2 is a cross-sectional view of the optical beam splitter provided in the first embodiment, wherein the upper surface is represented as an optical refractive surface having different inclination angles, and S0-S5 are formed by parallel beams passing through the optical beam splitter. A split beam of light in different directions, the material of the beam splitter being optical glass quartz with a refractive index n=1.45.

Please refer to FIG. 3 and FIG. 4 , which are top views of each of the optical splitting units in the optical beam splitter according to the embodiment.

In this embodiment, the refractive surfaces in each of the optical splitting units are inclined in different directions to form a 2*2 optical beam splitter, and the tilt angle θi of each optical refractive surface in each optical splitting unit is 43 degrees. According to the following formula, the optical splitting half angle α is 38.45 degrees, and the formed 2*2 splitting full angle is 76.9 degrees. The applicable band is from near ultraviolet to near infrared.

Sin θo=n sin θi

α=θo-θi

Example 2:

5 is a cross-sectional view of the optical beam splitter according to Embodiment 2, wherein the upper surface is represented as an optical refractive surface having different inclination angles, and S0-S5 are formed by parallel beams passing through the optical beam splitter. A split beam of light in different directions, the material of which is optical glass D-ZK3, refractive index n = 1.59.

Please refer to FIG. 6 and FIG. 7 , which are top views of each of the optical splitting units in the optical beam splitter according to the embodiment.

In this embodiment, the refractive surfaces in each of the optical splitting units are inclined in different directions to form a 3*3 optical beam splitter, and the tilt angle θi of each optical refractive surface in each optical splitting unit is 38 degrees. According to the following formula, the optical splitting half angle α is obtained as 40.2 degrees, and the formed 3*3 splitting full angle is 80.4 degrees, and the applicable wavelength band is from near ultraviolet to near infrared.

Sin θo=n sin θi

α=θo-θi

Example 3:

5 is a cross-sectional view of the optical beam splitter according to Embodiment 3, wherein the upper surface is represented as an optical refractive surface having different oblique angles, and S0-S5 are formed by parallel beams passing through the optical beam splitter. A split beam of light in different directions, the material of the beam splitter being an optical plastic polycarbonate having a refractive index n = 1.585.

Please refer to FIG. 8 , which is a top view of each optical splitting unit in the optical beam splitter provided by this embodiment.

In this embodiment, the refractive surfaces in each of the optical splitting units are inclined in different directions to form a 4*4 optical beam splitter, and the tilt angle θi of each optical refractive surface in each optical splitting unit is 39 degrees. According to the following formula, the optical splitting half angle α is 46.92 degrees, and the formed 4*4 splitting full angle is 93.84 degrees, and the applicable wavelength band is visible light and near infrared.

Sin θo=n sin θi

α=θo-θi

Example 4:

2 is a cross-sectional view of the optical beam splitter according to Embodiment 4, wherein the upper surface is represented as an optical refractive surface having different inclination angles, and S0-S5 are formed by parallel beams passing through the optical beam splitter. A beam splitting beam of different directions, the material of which is an optical plastic polymethyl methacrylate with a refractive index n=1.49.

Please refer to FIG. 9 , which is a top view of each of the optical splitting units in the optical beam splitter provided by this embodiment.

In this embodiment, the refractive surfaces in each of the optical splitting units are inclined in different directions to form a 5*5 optical beam splitter, and the tilt angle θi of each of the optical refractive surfaces in each of the optical splitting units is 42 degrees. According to the following formula, the optical splitting half angle α is 43.56 degrees, and the formed 5*5 splitting full angle is 87.12 degrees, and the applicable wavelength band is visible light and near infrared.

Sin θo=n sin θi

α=θo-θi

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

An optical beam splitter, characterized in that the optical beam splitter comprises a plurality of optical splitting units, each of the optical splitting units being composed of a plurality of optically refractive surfaces of different directions, each of the optical refractions The face meets the following relationship:

Each of the optical refractive surfaces refracts the incident parallel light to a different direction to form a split beam, and the splitting angle α of the split beam satisfies the following relationship:

Sin θo=n sin θi

α=θo-θi

Where n is the refractive index of the material constituting the optical refractive surface, θi is the angle between the optical refractive surface and the plane perpendicular to the incident light, and θo is the angle of refraction after the light passes through the optical refractive surface.
The optical beam splitter according to claim 1, wherein each of said optical refractive surfaces refractions the incident parallel light to a different direction to form a beam spot of the beam spot incident on the target surface. The beam spot corresponds to a refractive surface that is proportional to a projected area perpendicular to the plane of the incident light.
The optical beam splitter according to claim 1, wherein the material of the optical beam splitter is an optical plastic or an optical glass.
The optical beam splitter according to claim 1, wherein each of said optical splitting units has a lateral dimension smaller than an incident beam spot size such that said incident beam completely covers said beam splitting unit at least completely.
The optical beam splitter according to claim 1, wherein each of said optical splitting units is arranged in a periodic array.
The optical beam splitter according to claim 1, wherein the beam split by said beam splitter forms a regular splitting arrangement on the target surface.
The optical beam splitter according to claim 1, wherein the beam split by said beam splitter forms a random splitting arrangement on the target surface.
An optical device comprising the optical beam splitter of claim 1.