阅读说明：本技术 一种玻塑混合的全景环带成像装置 (Panoramic annular belt imaging device with glass and plastic mixed ) 是由 冯逸鹤 王佳 王之丰 白剑 于 2021-07-27 设计创作，主要内容包括：本发明公开了一种玻塑混合的全景环带成像装置,包括依次同轴设置的全景头部块状单元、孔径光阑、后继透镜组和探测器；所述全景头部块状单元靠近物面的表面包括外凸的前折射面,所述前折射面中部设置外凸的前反射面；全景头部块状单元靠近像面的表面包括外凸的后反射面,所述后反射面中部设置外凸的后折射面；所述全景头部块状单元采用非球面的塑料单镜片,后继透镜组包含非球面的塑料镜片和球面的玻璃镜片；光线依次通过全景头部块状单元的前折射面、后反射面、前反射面、后折射面后,再通过孔径光阑进入后继透镜组,并到达探测器像面形成像。(The invention discloses a glass-plastic mixed panoramic annular belt imaging device, which comprises a panoramic head block unit, an aperture diaphragm, a subsequent lens group and a detector which are coaxially arranged in sequence; the surface of the panoramic head block unit close to the object surface comprises a convex front refraction surface, and the middle part of the front refraction surface is provided with a convex front reflection surface; the surface of the panoramic head block unit close to the image surface comprises a convex rear reflecting surface, and the middle part of the rear reflecting surface is provided with a convex rear refracting surface; the panoramic head block-shaped unit adopts an aspheric plastic single lens, and the subsequent lens group comprises an aspheric plastic lens and a spherical glass lens; the light rays sequentially pass through the front refraction surface, the rear reflection surface, the front reflection surface and the rear refraction surface of the panoramic head block unit, then enter the subsequent lens group through the aperture diaphragm and reach the detector for imaging the image surface shape.)

1. A glass-plastic mixed panoramic annular imaging device is characterized by comprising a panoramic head block unit, an aperture diaphragm, a subsequent lens group and a detector which are coaxially arranged in sequence; the surface of the panoramic head block unit close to the object surface comprises a convex front refraction surface, and the middle part of the front refraction surface is provided with a convex front reflection surface; the surface of the panoramic head block unit close to the image surface comprises a convex rear reflecting surface, and the middle part of the rear reflecting surface is provided with a convex rear refracting surface; the panoramic head block-shaped unit adopts an aspheric plastic single lens, and the subsequent lens group comprises an aspheric plastic lens and a spherical glass lens; the light rays sequentially pass through the front refraction surface, the rear reflection surface, the front reflection surface and the rear refraction surface of the panoramic head block unit, then enter the subsequent lens group through the aperture diaphragm and reach the detector for imaging the image surface shape.

2. A glass-plastic hybrid panoramic annular imaging apparatus according to claim 1, wherein the radius of curvature and aspheric coefficients of the rear reflecting surface and the rear refracting surface are equal.

3. A glass-plastic hybrid panoramic annular imaging device according to claim 1, wherein the subsequent lens group comprises a plurality of single lenses, a plurality of cemented lenses; the single lens and the cemented lens are made of plastic or glass, and the surface types of the single lens and the cemented lens are standard spherical surfaces or aspheric surfaces.

4. The glass-plastic hybrid panoramic annular imaging device according to claim 1, wherein an image formed on the image surface of the detector is in an annular belt shape, a central circle of the annular belt shape is a blind area, and the annular belt area of the annular belt shape corresponds to the panoramic field of view.

Technical Field

The invention relates to the technical field of imaging lenses, in particular to a glass-plastic mixed panoramic annular imaging device.

Background

The panoramic annular imaging device has wide application value in the aspects of security monitoring, pipeline endoscopy, machine vision and video conference, and comprises a panoramic head block unit, a follow-up lens group and a detector, wherein the maximum aperture is positioned in the panoramic head block unit. The head unit of the existing panoramic annular imaging device is mostly composed of spherical surface type glass lenses or aspheric surface double reflectors, and the form that the whole panoramic head unit is made of aspheric surface plastic materials does not exist, so that the structure of the whole system is not compact enough, and the panoramic annular imaging device cannot be applied to the field of a plurality of size limitations.

The panoramic head block-shaped unit of the existing aspheric panoramic annular imaging device mainly adopts several aspheric forms in a follow-up lens group. For example, patent publication No. CN206161948U discloses a panoramic lens, which comprises, in order from an object, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens, wherein the first lens is a glass lens with negative focal power, and the object-side surface of the first lens is a convex surface; the second lens is a meniscus plastic lens which has negative focal power and is convex to the object space; the third lens is a glass lens with positive focal power and double convex surfaces; the fourth lens is a glass lens with positive focal power and double convex two surfaces; the fifth lens is a meniscus glass lens with negative focal power and convex to the image space, and the fourth lens and the fifth lens are cemented lenses; the sixth lens is a double convex plastic lens with positive focal power and two aspheric surfaces. Although the above patent can improve the pixels of the panoramic lens, the head unit is composed of spherical surface type glass lenses, and compared with plastic materials, the glass materials have high cost, long production period, are not suitable for mass production, and have the problem that the structure of the whole system is not compact enough.

Most of materials adopted in the existing aspheric panoramic imaging device are glass lenses, so that in the double-reflector technology, the panoramic imaging device which completely uses aspheric surfaces on the refraction surface and the reflection surface of the panoramic head unit and adopts a plastic glass form has not been proposed yet, and the existing aspheric panoramic annular belt imaging device has the defects of large structural size, large blind area range, more lenses of the follow-up lens group and inconvenience for use in scenes with multiple size limitations.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a glass-plastic mixed panoramic annular belt imaging device which is simpler in structure, smaller in size and blind area and suitable for mass production.

In order to achieve the purpose, the invention adopts the following technical scheme:

a glass-plastic mixed panoramic annular imaging device comprises a panoramic head block unit, an aperture diaphragm, a subsequent lens group and a detector which are coaxially arranged in sequence; the surface of the panoramic head block unit close to the object surface comprises a convex front refraction surface, and the middle part of the front refraction surface is provided with a convex front reflection surface; the surface of the panoramic head block unit close to the image surface comprises a convex rear reflecting surface, and the middle part of the rear reflecting surface is provided with a convex rear refracting surface; the panoramic head block-shaped unit adopts an aspheric plastic single lens, and the subsequent lens group comprises an aspheric plastic lens and a spherical glass lens; the light rays sequentially pass through the front refraction surface, the rear reflection surface, the front reflection surface and the rear refraction surface of the panoramic head block unit, then enter the subsequent lens group through the aperture diaphragm and reach the detector for imaging the image surface shape.

Furthermore, the curvature radius and the aspheric surface coefficient of the rear reflecting surface and the rear refracting surface are equal.

Further, the subsequent lens group comprises a plurality of single lenses and a plurality of cemented lenses; the single lens and the cemented lens are made of plastic or glass, and the surface types of the single lens and the cemented lens are standard spherical surfaces or aspheric surfaces.

Furthermore, an image formed on the image surface of the detector is in an annular belt shape, the center circle of the annular belt shape is a blind area, and the annular belt area of the annular belt shape corresponds to the panoramic view field.

Compared with the prior art, the invention has the following beneficial effects:

1. the aspheric panoramic head block-shaped unit can simplify the structure of the panoramic lens, reduce the size of the whole lens and reduce the using number of lenses, thereby reducing the processing cost. In addition, compared with a glass material, the plastic material is lower in cost for mass production.

2. Aspheric surfaces have a stronger ability to correct aberrations than spherical surfaces. For a large field of view optical lens such as a panoramic annular lens, the aperture of the first lens is usually the largest in the whole system. The aspheric surface-shaped panoramic head block-shaped unit can transmit light with a large field of view under a relatively small caliber, so that the lens can be applied to a scene with limited size without obstacles.

3. The single-chip aspheric surface-shaped panoramic block-shaped unit is simpler in assembly, and compared with a glued panoramic block, the coating is simpler.

Drawings

FIG. 1 is a block diagram of a glass-plastic hybrid panoramic annular imaging device according to one embodiment;

fig. 2 is a surface labeled diagram of a panoramic block-shaped head unit provided in the first embodiment.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict.

The invention aims to overcome the defects of the prior art and provides a glass-plastic mixed panoramic annular imaging device.

Example one

The embodiment provides a glass-plastic mixed panoramic annular imaging device, as shown in fig. 1-2, comprising a panoramic head block unit 11, an aperture stop S5, a subsequent lens group 12 and a detector 13 which are coaxially arranged in sequence; the light rays sequentially pass through the panoramic head block unit 11, the aperture diaphragm and the subsequent lens group 12 and then reach the detector 13 for imaging the image surface shape.

The surface of the panoramic head block unit 11 close to the object surface comprises a convex front refraction surface S1, and the middle part of the front refraction surface is provided with a convex front reflection surface S3; the surface of the middle part of the panoramic head block unit, which is close to the image surface, comprises a convex rear reflecting surface S2, the middle part of the rear reflecting surface is provided with a convex rear refracting surface S4, and the curvature radiuses of the rear reflecting surface S2 and the rear refracting surface S4 are equal to the aspheric surface coefficient; in this embodiment, the surface of the panoramic head block unit near the image plane except for the middle portion is a plane. The panoramic head block unit 11 is made of an aspheric plastic single lens, specifically, the front refracting surface S1, the rear reflecting surface S2, the front reflecting surface S3 and the rear refracting surface S4 are aspheric surfaces, and the practical material of the panoramic head block unit 11 is plastic.

The subsequent lens group 12 comprises an aspherical plastic lens and a spherical glass lens; specifically, the subsequent lens group 12 includes a plurality of single lenses and a plurality of cemented lenses; the single lens and the cemented lens are made of plastic or glass, and the surface type of the single lens and the cemented lens is a standard spherical surface or an aspheric surface.

The image formed by the image surface of the detector 13 is in the shape of an annular band, the center circle of the annular band is a blind area, and the annular band area of the annular band corresponds to the panoramic view field, namely the size of the area of the annular band corresponds to the size of the view field range and the focal length of the panoramic annular band imaging device.

After the light rays sequentially pass through the front refracting surface S1, the rear reflecting surface S2, the front reflecting surface S3 and the rear refracting surface S4 of the panoramic head block-shaped unit, the light rays pass through the aperture stop STO, enter the subsequent lens group 12 through a small-field light path, and reach the detector 13 for imaging the image surface shape.

It should be noted that, in this embodiment, only the panoramic head block-shaped head unit is set to be an aspheric plastic monolithic structure, and the number, position, type, material, and the like of the remaining lenses are not limited.

This embodiment will be described in detail with an example in which the relay lens group 12 includes 7 lenses.

As shown in fig. 1, the present embodiment includes 8 lenses and an image plane in total, and the 8 lenses are lens G1 of the panoramic head block unit, a biconvex lens G2, a biconcave lens G3, a biconvex lens G4, a meniscus lens G5, a biconcave lens G6, a meniscus lens G7, and a biconvex lens G8 in this order; the double-concave lens G3 and the double-convex lens G4 form a cemented wafer through gluing, and the rest lenses are single lenses; the data of the shots are shown in table 1 below.

The field angle of the panoramic annular imaging device is (50-135 degrees) multiplied by 360 degrees, the working waveband is a visible light waveband, and the number of the image F is 2.5; the focal length is-0.83 mm, the entrance pupil diameter is 0.3mm, and the total length is 58 mm.

TABLE 1 lens data

In order to realize imaging with an ultra-large field of view, all four surfaces of the head unit adopt an aspheric form. The subsequent lens group comprises an aspheric plastic lens and a spherical glass lens, so that glass-plastic hybrid imaging is realized, the volume of the device is reduced, and the device can be applied to a plurality of scenes for limiting the size of a lens; the plastic has low cost and is suitable for mass production.

The glass-plastic mixed panoramic annular imaging device does not limit the number of lenses, the using position of an aspheric surface, the using type of the aspheric surface, glass and plastic materials and the number of gluing parts, and only protects the head block-shaped head unit from using aspheric plastic.

This embodiment uses an aspherical surface type which can provide more optimization variables than a spherical surface type. The reduction of the number of lenses is not only due to the use of a plastic single-lens head unit, but also related to a subsequent lens group, and the head unit comprises four surfaces, two transmission surfaces and two reflection surfaces, wherein all the four surfaces are aspheric surfaces, so that more optimization variables are added.

Compared with the prior art, the embodiment has the following beneficial effects:

1. the aspheric panoramic head block-shaped unit can simplify the structure of the panoramic lens, reduce the size of the whole lens and reduce the using number of lenses, thereby reducing the processing cost. In addition, compared with a glass material, the plastic material is lower in cost for mass production.

2. Aspheric surfaces have a stronger ability to correct aberrations than spherical surfaces. For a large field of view optical lens such as a panoramic annular lens, the aperture of the first lens is usually the largest in the whole system. The aspheric surface-shaped panoramic head block-shaped unit can transmit light with a large field of view under a relatively small caliber, so that the lens can be applied to a scene with limited size without obstacles.

3. The single-chip aspheric surface-shaped panoramic block-shaped unit is simpler in assembly, and compared with a glued panoramic block, the coating is simpler;

4. this embodiment adopts the monolithic lens to solve the problem that the biplate lens is difficult to use aspheric surface face type, and has also solved the biplate lens and will make two lens veneer, needs very high central positioning technique, and hardly realizes the accurate problem of veneer, and the head unit of this single lens is the effect that can realize the biplate lens.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.