CN102789114B - Visible-infrared bi-pass camera - Google Patents

Abstract

The invention discloses a visible-infrared dual-pass camera, comprising: an imaging device, an infrared optical path, a visible light optical path, an FPA chip, a visible light reading optical path, and an optical receiver; the imaging device includes: a visible-infrared imaging objective lens, a visible-infrared The imaging objective lens includes: a spectroscopic device; the imaging device images the infrared light obtained by splitting the spectroscopic device on the FPA chip through the infrared optical path, and the visible light reading path reads the image information on the FPA chip and reflects the image information on the optical receiver Above; the imaging device images the visible light split by the beam splitter on the optical receiver through the visible light path. The visible-infrared dual-pass camera disclosed in the embodiment of the present invention realizes the separation of visible light and infrared light in the optical path space through a spectroscopic device, and uses an FPA chip to realize infrared light imaging. display on the device, reducing system cost while reducing power consumption.

Description

A Visible-Infrared Dual-Pass Camera

technical field

The invention relates to the technical field of imaging instruments, in particular to a visible-infrared dual-pass camera.

Background technique

With the increasing popularity of monitoring and camera systems in the commercial and civilian fields, infrared cameras (surveillance cameras) are widely used in various fields to protect social security. For each different application field, different types of surveillance cameras are required to meet the requirements. As the public has higher and higher requirements for monitoring products, such as 24-hour monitoring and low prices, in order to adapt to changes in market demand, manufacturers are competing to develop visible and infrared day and night dual-purpose cameras.

At present, domestic day and night cameras still need to be equipped with certain lighting equipment or infrared equipment, and use the optical path system that can simultaneously image infrared light and visible light and the receiver that responds to both infrared and visible light to detect and realize active infrared image video. collection. The above-mentioned design results increase the overall power consumption of the system, and the influence of infrared light on the optical system needs to be considered during design and processing, which greatly increases the cost of the main body of the optical path.

Contents of the invention

In view of this, the present invention provides a visible-infrared dual-pass camera, the specific scheme of which is as follows:

A visible-infrared dual-pass camera, comprising: an imaging device, an infrared optical path, a visible light optical path, an infrared focal plane array FPA chip, a visible light reading optical path, and an optical receiver;

Wherein, the imaging device includes: a visible-infrared imaging objective lens, and the visible-infrared imaging objective lens includes: a spectroscopic device that separates visible light and infrared light in optical path space;

The imaging device images the infrared light obtained by splitting the spectroscopic device on the FPA chip through the infrared optical path, and the visible light reading optical path reads the image information on the FPA chip, and converts the image information is reflected on said optical receiver;

The imaging device images the visible light split by the beam splitter on the optical receiver through the visible light path.

Preferably, the spectroscopic device includes: a dual bandpass filter, the dual bandpass filter is an infrared light filter and a visible light filter that can be moved in or out in the optical path;

When the infrared light filter is moved into the optical path and the visible light filter is moved out of the optical path, the imaging device, the infrared optical path, the FPA chip, the visible light reading optical path and the optical receiver form an infrared optical path;

When the visible light filter moves into the light path and the infrared light filter moves out of the light path, the imaging device, visible light light path, visible light reading light path and optical receiver form a visible light light path.

Preferably, the imaging device further includes: a far-infrared-visible filter capable of transmitting infrared light while reflecting visible light;

A visible-infrared imaging eyepiece lens that images the infrared beam passing through the far-infrared-visible filter on the FPA chip.

Preferably, the visible light path includes: a visible light bandpass filter and a right-angle reflective prism;

The transmission surface of the right-angle reflective prism is coated with an anti-reflection film, and the two reflection surfaces are coated with an anti-reflection film layer.

Preferably, the infrared light path includes:

An incoherent area light source with a small hole point light source filter, the incoherent area light source is filtered by the small hole to form a point light source;

A collimating lens that converts the light emitted by the point light source into parallel light.

Preferably, the visible light reading optical path includes: a cubic beamsplitter prism, a Fourier transform lens, a spectrum filter and an imaging lens, wherein:

The surface of the cubic dichroic prism is coated with a semi-reflective and semi-transparent film layer corresponding to the wavelength of the point light source;

The Fourier transform lens is used to realize the conversion of the image and the spectrum, and converts the light intensity information of the image on the FPA chip into spectrum information at a distance of one times the focal length of the Fourier transform lens;

The spectrum filter is provided with a translation structure capable of translating in the direction perpendicular to the optical path. When the infrared light filter moves into the optical path to form an infrared light path, the spectrum filter moves into the optical path through the translation structure and receives all The spectrum information converted by the Fourier transform lens is filtered and then imaged on the optical receiver through the imaging lens. When the visible light filter moves into the optical path to form the visible light path, the spectral filter passes through the A translating structure moves out of the light path.

Preferably, the distance between the FPA chip and the Fourier transform lens, and the distance between the Fourier transform lens and the spectrum filter are all within the range of the Fourier transform lens focal length;

The distance between the spectrum filter and the imaging lens, and the distance between the imaging lens and the optical receiver are both the focal length of the imaging lens.

It can be seen from the above-mentioned technical scheme that the visible-infrared dual-pass camera disclosed in the embodiment of the present invention realizes the separation of visible light and infrared light in the optical path space through the spectroscopic device arranged in the visible-infrared imaging objective lens, and utilizes FPA The chip realizes infrared light imaging, reads the imaging information through the visible light reading path and displays it on the optical receiver, so that the infrared light imaging process can use the optical receiver that only responds to visible light, without using both infrared and visible light Responsive receivers detect without considering the influence of infrared light on the optical system, which reduces system cost and power consumption.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the 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. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic structural view of the visible-infrared dual-pass camera disclosed in this embodiment;

FIG. 2 is a schematic structural diagram of another visible-infrared dual-pass camera disclosed in this embodiment;

FIG. 3 is a schematic structural diagram of another visible-infrared dual-pass camera disclosed in this embodiment.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The present invention is a visible-infrared dual-pass camera disclosed in an embodiment. Its structure is shown in FIG. 15 and optical receiver 16.

Wherein, the imaging device 11 includes: a visible-infrared imaging objective lens, and the visible-infrared imaging objective lens includes: a spectroscopic device that separates visible light and infrared light in the optical path space, and the imaging device 11 splits the light of the spectroscopic device The obtained infrared light is imaged on the FPA chip through the infrared optical path, and the visible light reading optical path reads the image information on the FPA chip, and reflects the image information on the optical receiver; The imaging device images the visible light split by the beam splitter on the optical receiver through the visible light path.

The FPA chip in this embodiment is a dual-material chip based on thermomechanical principles. It is packaged in a vacuum chamber and treated at a constant temperature in order to control the temperature of the chip and protect it from the influence of the external environment temperature, so as to better ensure its mechanical response. It is aimed at the thermal radiation of the monitoring target, reducing the mechanical deformation caused by other external factors, so that the thermomechanical deformation of the FPA chip can better reflect the situation of the monitoring target itself, and improve the accuracy of imaging. The optical receiver is an optical receiver that only responds to visible light.

The visible-infrared dual-pass camera disclosed in this embodiment realizes the separation of visible light and infrared light in the optical path space through the spectroscopic device arranged in the visible-infrared imaging objective lens, and uses the FPA chip to realize infrared light imaging, and reads the visible light through visible light. The optical path reads the imaging information and displays it on the optical receiver, so that the imaging process of infrared light can use the optical receiver that only responds to visible light, without using a receiver that responds to both infrared light and visible light for detection, reducing the system cost while reducing power consumption.

Furthermore, since different light rays correspond to different optical paths, the high standard requirements for the optical path system in the prior art that simultaneously image infrared light and visible light are resolved, and the processing difficulty and cost of the optical path components are reduced.

The structure of another visible-infrared dual-pass camera disclosed in the embodiment of the present invention is shown in Figure 2, including: an imaging device 21, an infrared optical path 22, a visible light optical path 23, an infrared focal plane array FPA chip 24, and a visible light reading optical path 25 and optical receiver 26.

Wherein, the imaging device 21 includes a visible-infrared imaging objective lens 211, and the spectroscopic device in the visible-infrared imaging objective lens 211 includes: a double bandpass filter, which can be moved in or out in the optical path Infrared light filter and visible light filter, when the infrared light filter moves into the optical path and the visible light filter moves out of the optical path, the imaging device, infrared optical path 22, FPA chip 24, visible light reading optical path 25 and light receiving The device 26 forms an infrared light path; when the visible light filter moves into the light path and the infrared light filter moves out of the light path, the imaging device, the visible light path 23, the visible light reading path 24 and the optical receiver 26 form a visible light path .

The imaging device 21 also includes: a far-infrared-visible filter 212 and a visible-infrared imaging eyepiece lens 213 . The far-infrared-visible filter 212 can transmit infrared light while reflecting visible light, and can transmit 8-14um infrared light while reflecting visible light; the visible-infrared imaging eyepiece lens 213 will image the infrared light beam passing through the far-infrared-visible filter On the FPA chip 24 , the visible light reflected by the far-infrared-visible filter 212 is imaged on the optical receiver 26 .

Further, the visible light path 23 includes: a visible light bandpass filter 231 and a right-angle reflective prism 232 ; the transmission surface of the right-angle reflective prism 232 is coated with an anti-reflection film, and the two reflective surfaces are coated with an anti-reflection film.

The infrared light path 22 includes: an incoherent area array light source 221 and a collimating lens 222, the incoherent area array light source 221 has a pinhole point light source filter, and the incoherent area array light source 221 is formed by filtering the pinhole A point light source; the collimating lens 222 converts the light emitted by the point light source into parallel light.

The visible light reading optical path 25 includes: a cubic dichroic prism 251 , a Fourier transform lens 252 , a spectrum filter 253 and an imaging lens 254 . The cubic dichroic prism 251 spatially deflects the light reflected and transmitted by the right-angle reflective prism, so that the visible light can pass through the visible light reading optical path and finally be received by the light receiver, and the collimated light in the visible light reading optical path is spatially deflected It is incident on the FPA chip, and at the same time, the reflected light of the chip can enter the visible light reading optical path through the cubic beam splitter again and finally be received by the light receiver. While realizing its basic functions, this component greatly compresses the optical path and reduces the volume of the system. The Fourier transform lens 252 realizes the conversion of the image and the frequency spectrum, and converts the light intensity information of the FPA image into spectral information at a distance of twice the focal length of the Fourier transform lens, that is, on the spectrum plane of the spectrum filter 253 , the spectral filter 253 is provided with a translational structure capable of translation in the direction perpendicular to the optical path, when the infrared light filter moves into the optical path to form an infrared optical path, the spectral filter 253 moves into the optical path through the translational structure, receiving The Fourier transform lens 252 converts the spectrum information, and filters out the light reflected from the FPA frame part with a frequency different from the spectrum of the reflection surface, and then passes the filtered light through the imaging lens 244 in the optical receiver 26 For imaging, the rays of the same spectrum ideally intersect at one point, but the actual optical path is a spot, and the incident light at different angles, that is, the spatial frequency, is located at different positions in the spectrum. Due to the thermomechanical deformation of the FPA, each pixel absorbs heat When deflection occurs at a certain angle, its spectral position will also undergo a certain displacement as the temperature changes, so the light intensity after passing through the spectral filter 253 will change, and this change will be received by the optical receiver 26, and the The heat-induced deformation of FPA is restored to light intensity to obtain an infrared image. When the visible light filter is moved into the optical path to form the visible light path, the spectrum filter 253 is moved out of the optical path through the translation structure, without processing the visible light, and the visible light is directly imaged on the optical receiver through the imaging lens.

In the above structure, the FPA chip 24 , the Fourier transform lens 252 , the spectrum filter 253 , the imaging lens 254 and the optical receiver 26 form a typical 4f system. Wherein, the distance between FPA chip 24 and Fourier transform lens 252, and the distance between Fourier transform lens 252 and spectrum filter 253 are the focal length of Fourier transform lens 252, and described spectrum filter 253 and The distance between the imaging lenses 254 and, the distance between the imaging lenses 254 and the optical receiver 26 is the focal length of the imaging lenses 254 .

The operating principle of the visible-infrared dual-pass camera disclosed in this embodiment is as follows:

In this embodiment, when the infrared filter moves into the optical path and the visible filter moves out of the optical path, the visible-infrared imaging objective lens 211 with the infrared filter, the far-infrared-visible filter 212, and the visible-infrared imaging eyepiece Lens 213, FPA chip 24, incoherent area array light source 221, collimator lens 222, cube beam splitter 251, Fourier transform lens 252, spectrum filter 253, imaging lens 254 and optical receiver 26 form infrared optical path, this optical path It can work in the night vision function or the environment with weak visible light. At this time, the infrared light filter of the visible-infrared imaging objective lens 211 passes the infrared light. The far-infrared-visible filter 212 transmits infrared light, and uses the visible-infrared imaging eyepiece lens 213 to form an image on the FPA chip 24. The incoherent surface light source 221 forms a point light source after passing through the pinhole filter, and the light beam of the point light source passes through the collimating lens. Afterwards, it becomes a collimated parallel light beam, which is deflected and incident on the FPA chip 24 by the cubic beam splitter 251. Since the back of the FPA chip 24 absorbs infrared light and produces a thermal effect, the reflective surface of the cantilever beam based on the double material will produce a certain angle. Therefore, the light beam reflected by the reflective surface will produce a certain angle of deviation, and the Fourier transform lens 252 will convert the frequency spectrum of the received light beam with angle deviation into the frequency spectrum at the position of the spectrum filter 253 , the spectrum filter 253 can filter out the light reflected from the FPA frame part with a frequency different from the spectrum of the reflective surface, and when the beam angle shifts, because its spectrum position will move with the change of the angle, it can pass The luminous flux of the filter 253 will also change accordingly, resulting in a change in the gray level of the light intensity signal received by the optical receiver 26 compared with the image collected at the reference time point, that is, when there is no angle change , using the gray level change, infrared light imaging can be obtained.

When the visible light filter is moved into the light path, and the infrared light filter is moved out of the light path, the visible-infrared imaging objective lens 211, the far infrared-visible filter 212, the visible-infrared imaging eyepiece lens 213, and the visible light bandpass filter with the visible light filter The sheet 231 , the rectangular reflective prism 232 , the cubic dichroic prism 251 , the Fourier transform lens 252 , the imaging lens 254 and the light receiver 26 form a visible light path. The visible light filter of the visible-infrared imaging objective lens 211 passes through visible light, and the visible light is reflected by the far-infrared-visible filter 212 and passes through the visible light bandpass filter 231 to retain the visible light with the same wavelength as the incoherent area light source and filter out other wavelengths The visible light is transmitted to the cubic dichroic prism 251 after two reflections by the right-angle reflective prism 232, and then reflected by the fourier transform lens 252 and the imaging lens 254 to form an image on the light receiver 26.

It can be seen from the above working principle that the above two optical paths work in different environments and time periods. When the imaging observation is carried out under the condition of better daytime light, the visible light filter of the visible-infrared imaging objective lens 211 is moved into the optical path; When the infrared night vision function is turned on, the infrared light filter of the visible-infrared imaging objective lens 211 moves into the light path to allow infrared rays to enter, and the day and night dual vision function is realized through the conversion operation of the double bandpass filter.

This embodiment does not limit the light-splitting device to be a dual-bandpass filter, and it may also be a device capable of light-splitting, such as a grating or a prism.

Based on the above-mentioned working principle, the structure of another visible-infrared dual-pass camera disclosed in the embodiment of the present invention is shown in Figure 3, and its basic structure is the same as that shown in Figure 2, except that the frequency ranges of the light transmission and reflection of the filter are different And adjusted accordingly.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for the related information, please refer to the description of the method part.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (7)

1. visible-infrared bilateral video camera, is characterized in that, comprising: imaging device, infrared light path path, visible ray light path path, infrared focal plane array FPA chip, visible ray read light path and optical receiver;

Wherein, described imaging device comprises: visible-infrared imaging objective lens, and as seen described-infrared imaging objective lens comprises: optical splitter visible ray and infrared light are separated on optical path space;

The infrared light that described optical splitter light splitting obtains by described imaging device is imaged on described FPA chip by described infrared light path, the light path that reads described visible ray reads the image information on described FPA chip, and by described image information reaction on described optical receiver;

The visible ray that described optical splitter light splitting obtains by described imaging device is imaged on described optical receiver by described visible ray light path path;

Optical receiver after above-mentioned infrared light light path path and the optical receiver after visible ray light path path are same optical receiver;

Described optical receiver is for only carrying out corresponding optical receiver to visible ray.

2. video camera according to claim 1, is characterized in that, described optical splitter comprises: dual band pass optical filter, and described dual band pass filtering mating plate is the infrared light filter plate and visible ray filter plate that can move in the optical path or shift out;

When described infrared light filter plate moves in light path, when described visible ray filter plate shifts out light path, described imaging device, infrared light path path, FPA chip, visible ray read light path and optical receiver composition infrared light light path;

When described visible ray filter plate moves in light path, when described infrared light filter plate shifts out light path, described imaging device, visible ray light path path, visible ray read light path and optical receiver composition visible ray light path.

3. video camera according to claim 2, is characterized in that, described imaging device also comprises: can the far infrared-visible filter plate of transmitted infrared light simultaneously reflect visible light;

Infrared light through described far infrared-visible filter plate is imaged on described FPA chip visible-infrared imaging eyepiece camera lens.

4. video camera according to claim 3, is characterized in that, described visible ray light path path comprises: visible band pass filter and right-angle reflecting prism;

The transmission surface of described right-angle reflecting prism is coated with anti-reflection film, and two reflectings surface of described right-angle reflecting prism are coated with and increase anti-rete.

5. video camera according to claim 4, is characterized in that, described infrared light path path comprises:

With the incoherent area array light source of aperture pointolite wave filter, described incoherent area array light source forms a pointolite through described pin-hole filter-ing;

The light that described pointolite sends is become the collimation lens of directional light.

6. video camera according to claim 5, is characterized in that, described visible ray reads light path and comprises: cube Amici prism, Fourier transform lens, spectrum filter and imaging lens, wherein:

Described cube of Amici prism surface is coated with the transflective film corresponding with described pointolite wavelength;

The intensity signal of the image on described FPA chip, for realizing the conversion of image and frequency spectrum, is converted to spectrum information in the distance being doubled in described Fourier transform lens focal length by described Fourier transform lens;

Described spectrum filter is provided with can at the translation structure with translation in light path vertical direction, when described infrared light filter plate moves into light path composition infrared light path, described spectrum filter moves into light path by described translation structure, receive the spectrum information after the conversion of described Fourier transform lens, and by after its filtering by imaging lens imaging on described optical receiver, when described visible ray filter plate moves into light path composition visible ray light path, described spectrum filter shifts out described visible ray light path by described translation structure.

7. video camera according to claim 6, is characterized in that, the distance between described FPA chip and described Fourier transform lens, and the distance between described Fourier transform lens and described spectrum filter, is the focal length of described Fourier transform lens;

Distance between described spectrum filter and described imaging lens, and the distance between described imaging lens and described optical receiver, is the focal length of described imaging lens.