CN102645729A - Infrared optical system - Google Patents

Abstract

The invention discloses an infrared optical system, which is mounted on a photoelectric platform provided with an infrared focal plane detector and comprises a first lens system, a second lens system, a fly-back mirror and a third lens system. The fly-back mirror is positioned between the second lens system and the third lens system, both the first lens system and the second lens system have positive focal power, an image-side focal point F1 of the first lens system is coincided with an object-side focal point F2 of the second lens system, the first lens system and the second lens system form an infrared afocal system, and the fly-back mirror rotates around a self rotating shaft and realizes fly-back periodically. The infrared optical system receives the same scene information at infinity in integral time or at every moment within characteristic time, and a scene corresponding to the scene information is imaged on the infrared focal plane detector by the third lens system. The infrared optical system can solve the problem of image blurring when a photoelectric platform rotates at a fast speed, and has the advantages of small size, light weight, low cost and the like.

Description

A kind of infrared optical system

Technical field

The present invention relates to optical technical field, particularly relate to a kind of infrared optical system.

Background technology

Along with the development of infrared eye technology, infrared eye gets into the focal plane epoch.Because infrared focal plane device does not need the scanning mechanism just can be to the direct staring imaging of scenery, and the system architecture of employing focal plane device is simple, volume is little, therefore, is widely used in every field.In order to make infrared camera obtain higher sensitivity, the integral time of focal plane device or time constant are generally longer.Integral time or time constant are similar to the aperture time of visible light camera, and still, when parameter detector fixedly the time, integral time or time constant setting range are limited.

In order effectively to obtain bigger hunting zone in the time, the angular velocity of rotation of photoelectric platform (or turntable) is more and more faster, and 360 ° of panoramas are spliced by the multiple image with certain visual field.For the ease of the splicing of image, have certain overlapping between two width of cloth images.

Photoelectric platform searching moving fast causes scenery and infrared system to relatively move fast between the two, and long integral time or time constant cause infrared image fuzzy, has reduced the sensitivity and the resolution of infrared camera, and having limited it should have the field.

Summary of the invention

The technical matters that the present invention will solve provides a kind of infrared optical system, in order to solve image blurring problem in the prior art photoelectric platform fast rotational.

For solving the problems of the technologies described above, on the one hand, the present invention provides a kind of infrared optical system, and said infrared optical system is installed on the photoelectric platform that adopts infrared focal plane detector; Said infrared optical system comprises first lens combination, second lens combination, flyback mirror and the 3rd lens combination; Wherein, said flyback mirror is between said second lens combination and the 3rd lens combination; Said first lens combination, second lens combination all have positive light coke; And the rear focus F1 of said first lens combination overlaps with the focus in object space F2 of second lens combination; Said first lens combination, second lens combination constitute infrared afocal system; Said flyback mirror is around self turning axle rotation, cycle flyback; Said infrared optical system each in integral time or time constant constantly all receives the Same Scene information that is positioned at infinity, and by said the 3rd lens combination the infrared radiation of this scene is imaged in infrared focal plane detector.

Further, the equation of motion of said flyback mirror cycle flyback is:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000156515240000011.png,HDA0000156515240000021.png"\; state="\{\{state\}\}">f</figure-callout>}1}{2f2}\{{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}-\mathrm{INT}[\frac{360{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}}{n(1-\mathrm{\&beta;})}\left]\frac{{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}}{1000}\right\};$

Wherein, the position of flyback mirror was represented with angle when δ (t) express time was t; Z0 is the zero position of flyback mirror; T is the time; F1 is the focal length of first lens combination; F2 is the focal length of second lens combination; ω (t) is the function of photoelectric platform angular velocity of rotation and time t; τ is the integral time or the time constant of infrared focal plane detector; The scene number that n needs for the spliced panoramic image; β is the scene Duplication; INT is a bracket function.

Further, when photoelectric platform at the uniform velocity rotated with angular velocity omega, the equation of motion of flyback mirror cycle flyback was:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000156515240000011.png,HDA0000156515240000021.png"\; state="\{\{state\}\}">f</figure-callout>}1}{2f2}\{\mathrm{\&omega;t}-\mathrm{INT}[\frac{360\mathrm{\&omega;t}}{n(1-\mathrm{\&beta;})}\left]\frac{\text{\&omega;\&tau;}}{1000}\right\}.$

Further, said flyback mirror is positioned at the exit pupil position of infrared afocal system, and the entrance pupil position of said infrared afocal system is positioned on said first lens combination.

Further, the entrance pupil position of said the 3rd lens combination overlaps with the exit pupil position of said infrared afocal system.

Further, there is intermediate image face in said the 3rd lens combination, or does not have intermediate image face.

Further, the exit pupil position of said the 3rd lens combination overlaps with the cold stop of infrared focal plane detector.

Further, there is the catoptron with turnover light path in said the 3rd lens combination; Said flyback mirror also is used to the light path of turning back.

Further, said infrared optical system is applicable to non-refrigeration type or refrigeration mode infrared focal plane detector.

Further, said infrared optical system is applicable to shortwave, medium wave or LONG WAVE INFRARED focus planardetector.

Beneficial effect of the present invention is following:

Flyback mirror fast cycle of the present invention flyback makes infrared camera in whole integral time or time constant, stare Same Scene all the time, solves image blurring problem in the photoelectric platform fast rotational; The flyback mirror places the optics exit pupil position of infrared afocal system, makes its size minimum, and weight is the lightest, is convenient to servocontrol; The optics entrance pupil position of infrared afocal system is positioned on first lens combination, reduces infrared camera in the size perpendicular to optical axis direction, reduces the aperture amount aberration of optical system, dwindles its volume, reduces its cost; Flyback mirror and catoptron are turned back to light path, are convenient to the miniaturization of infrared camera.

Description of drawings

Fig. 1 is the optical schematic diagram of the infrared optical system during the photoelectric platform zero-bit in the embodiment of the invention;

The photoelectric platform of Fig. 2 Fig. 1 rotates the optical schematic diagram of a certain position, back;

Fig. 3 is the infrared optical system synoptic diagram of the embodiment of the invention 1 in the photoelectric platform zero-bit;

Fig. 4 is the embodiment of the invention 1 is rotated a certain position, back at photoelectric platform an infrared optical system synoptic diagram;

Fig. 5 is the embodiment of the invention 2 is learned system's small field of view state at the ruddiness of photoelectric platform zero-bit a synoptic diagram;

Fig. 6 is the embodiment of the invention 2 is rotated the ruddiness system small field of view state of a certain position, back at photoelectric platform a synoptic diagram;

Fig. 7 is the embodiment of the invention 2 is learned system's big visual field state at the ruddiness of photoelectric platform zero-bit a synoptic diagram;

Fig. 8 is the embodiment of the invention 2 is rotated the ruddiness system big visual field state of a certain position, back at photoelectric platform a synoptic diagram.

Embodiment

In order to solve image blurring problem in the prior art photoelectric platform fast rotational, the invention provides a kind of infrared optical system, below in conjunction with accompanying drawing and embodiment, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, does not limit the present invention.

As shown in Figure 1, the embodiment of the invention relates to a kind of infrared optical system, and this infrared optical system is installed on the quick search photoelectric platform 7 that adopts infrared focal plane detector, to promote the quick search capability of the photoelectric platform that adopts infrared focal plane detector.This infrared optical system comprises first lens combination 1, second lens combination 2, flyback mirror 3, the 3rd lens combination 4, and flyback mirror 2 is between second lens combination 2 and the 3rd lens combination 4; First lens combination 1, second lens combination 2 all have positive light coke.Focal power is the inverse of focal length, and positive light coke is exactly the inverse of positive focal length, and promptly positive light coke shows it is positive lens.The rear focus F1 of first lens combination 1 overlaps with the focus in object space F2 of second lens combination 2, forms infrared afocal system 8.Infrared afocal system is meant the system of directional light incident, parallel light emergence, is equivalent to telescope.Flyback mirror 3 is positioned at the exit pupil position of infrared afocal system 8; The entrance pupil position of infrared afocal system 8 is positioned on first lens combination 1; Each in integral time or time constant of the 3 fast cycle flybacks of flyback mirror, infrared optical system constantly all receives the Same Scene information that is positioned at infinity, and by the 3rd lens combination 4 infrared radiation of this scene is imaged in infrared focal plane detector; Flyback mirror 3 is around self turning axle rotation; Turning axle just is perpendicular to the straight line of flyback mirror 3 mid points; Among Fig. 1, turning axle is exactly perpendicular to the straight line of paper on the mid point of flyback mirror 3.The entrance pupil position of the 3rd lens combination 4 overlaps with the exit pupil position of infrared afocal system 8, and the exit pupil position of the 3rd lens combination 4 overlaps with the cold stop of infrared focal plane detector.Can there be intermediate image face in the 3rd lens combination 4, also can have intermediate image face; There is the catoptron with turnover light path in the 3rd lens combination 4.

As shown in Figure 2; When photoelectric platform 7 rotates to position B (position shown in Figure 2) process from zero-bit; Utilize the flyback effect of flyback mirror 3; In integral time or time constant each constantly, optical system all receives Same Scene 5 information that are positioned at infinity, and by lens combination 4 infrared radiation of scene 5 is imaged in infrared focal plane detector 6.Flyback mirror 3 plays the effect of the light path of turning back.

The equation of motion of flyback mirror 3 fast cycle flybacks is:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000156515240000011.png,HDA0000156515240000021.png"\; state="\{\{state\}\}">f</figure-callout>}1}{2f2}\{{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}-\mathrm{INT}[\frac{360{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}}{n(1-\mathrm{\&beta;})}\left]\frac{{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}}{1000}\right\};$

Wherein, the position of flyback mirror 3 was represented with angle when δ (t) express time was t; Z0 is the zero position of flyback mirror 3; T is the time; F1 is the focal length of first lens combination; F2 is the focal length of second lens combination; ω (t) is the function of photoelectric platform angular velocity of rotation and time; τ is the integral time or the time constant of infrared focal plane detector; The scene number that n needs for the spliced panoramic image; β is the scene Duplication; INT is a bracket function.

When photoelectric platform at the uniform velocity rotated with angular velocity omega, the equation of motion of flyback mirror fast cycle flyback was:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000156515240000011.png,HDA0000156515240000021.png"\; state="\{\{state\}\}">f</figure-callout>}1}{2f2}\{\mathrm{\&omega;t}-\mathrm{INT}[\frac{360\mathrm{\&omega;t}}{n(1-\mathrm{\&beta;})}\left]\frac{\text{\&omega;\&tau;}}{1000}\right\}.$

Above-mentioned infrared optical system is monoscopic or many visual fields system, belongs to optics continuous vari-focus system, is applicable to non-refrigeration type or refrigeration mode infrared focal plane detector, also is applicable to shortwave, medium wave or LONG WAVE INFRARED focus planardetector.

Be elaborated with two instantiations below:

Embodiment 1

Embodiment 1 is the infrared optical system that is applicable to the quick search photoelectric platform 7 of non-refrigeration type focal plane infrared eye.Fig. 3 is the infrared optical system synoptic diagram of photoelectric platform zero-bit, and Fig. 4 is the embodiment of the invention 1 is rotated a certain position, back at photoelectric platform an infrared optical system synoptic diagram.Lens combination (first lens combination) 1 is made up of lens 301,302, and lens combination (second lens combination) 2 is made up of lens 303,304, and the rear focus F1 of lens combination 1 overlaps with the focus in object space F2 of lens combination 2, and lens combination 1,2 is formed infrared afocal system 8; Flyback mirror 3 is positioned at infrared afocal system emergent pupil; Infrared afocal system 8 entrance pupil positions are positioned on the lens 301; Lens combination (the 3rd lens combination) 4 is made up of lens 305,306,307, and the entrance pupil position of lens combination 4 overlaps with the exit pupil position of infrared afocal system 8.Each in integral time or time constant of the 3 fast cycle flybacks of flyback mirror, infrared optical system all receives Same Scene 5 information that are positioned at infinity constantly, and is imaged on the infrared focal plane detector 6 by the infrared radiation of lens combination 4 with this scene.Flyback mirror 3 plays the effect of the light path of turning back simultaneously.The technical indicator of this embodiment is seen table one.

Table one

Service band	8μm～14μm
		The F number	0.9
Focal length	150mm
		The visual field	6°×4.5°
The maximum flyback angle of flyback mirror	3.6°
		Integral time (or time constant)	10ms
The scene Duplication	8.3％

Scene is counted n	65
		Lens combination 1 focal distance f 1	254mm
Lens combination 2 focal distance f 2	60mm

When photoelectric platform 7 at the uniform velocity rotated with angular velocity omega, the equation of motion of flyback mirror fast cycle flyback was:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000156515240000011.png,HDA0000156515240000021.png"\; state="\{\{state\}\}">f</figure-callout>}1}{2f2}\{\mathrm{\&omega;t}-\mathrm{INT}[\frac{360\mathrm{\&omega;t}}{n(1-\mathrm{\&beta;})}\left]\frac{\mathrm{\&omega;\&tau;}}{1000}\right\};$

Bring the parameter in the table one into above-mentioned equation, can obtain in this embodiment 1, the equation of motion of flyback mirror 3 fast cycle flybacks is:

$\mathrm{\&delta;}\left(t\right)=Z0+2\mathrm{\&omega;t}+\mathrm{INT}\left(6\mathrm{\&omega;t}\right)\frac{\mathrm{\&omega;}}{50}.$

Embodiment 2

Embodiment 2 is the infrared optical system of the quick search photoelectric platform of the infrared infrared eye in employing refrigeration mode focal plane, and this infrared optical system is the double-view field system.Fig. 5, Fig. 6 be under this instance small field of view state in integral time or time constant; The infrared optical system synoptic diagram of photoelectric platform different rotary position; Lens combination (first lens combination) 1 is made up of lens 501,502,503; Lens combination (second lens combination) 2 is made up of lens 504, and the rear focus F1 of lens combination 1 overlaps with the focus in object space F2 of lens combination 2, and lens combination 1,2 is formed infrared afocal system 8; Flyback mirror 3 is positioned at infrared afocal system 8 exit pupil positions; Lens combination (the 3rd lens combination) 4 is made up of lens 505,506,507,508 and catoptron 509; 510 is the window of refrigeration mode infrared focal plane detector, and 511 is the cold stop in the refrigeration mode infrared focal plane detector; Have intermediate image point I in the lens combination 4, there is conjugate relation in cold stop 511 with infrared afocal system 8 emergent pupils.Fig. 7, Fig. 8 be under the state of the big visual field of this instance in integral time or time constant, the infrared optical system synoptic diagram of photoelectric platform different rotary position.Under the small field of view state, cut lens 712,713, form the big visual field state of this instance.Each in integral time or time constant of the 3 fast cycle flybacks of flyback mirror, infrared optical system all receives Same Scene 5 information that are positioned at infinity constantly, and is imaged on the infrared focal plane detector 6 by the infrared radiation of lens combination 4 with this scene.The effect that flyback mirror 3 and catoptron 509 have light path to turn back.The technical indicator of this embodiment 2 is seen table two.

Table two

When photoelectric platform 7 at the uniform velocity rotated with angular velocity omega, the equation of motion of flyback mirror fast cycle flyback was:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{\mathrm{<figure-callout\; id="1"\; label="f"\; filenames="HDA0000156515240000011.png,HDA0000156515240000021.png"\; state="\{\{state\}\}">f</figure-callout>}1}{2f2}\{\mathrm{\&omega;t}-\mathrm{INT}[\frac{360\mathrm{\&omega;t}}{n(1-\mathrm{\&beta;})}\left]\frac{\mathrm{\&omega;t}}{1000}\right\};$

Bring the parameter in the table two into above-mentioned equation, can obtain respectively in this embodiment 2:

The equation of motion of flyback mirror 3 is under the small field of view state:

$\mathrm{\&delta;}\left(t\right)=z0+4.17\mathrm{\&omega;t}-\mathrm{INT}\left(3.05\mathrm{\&omega;t}\right)\frac{417\mathrm{\&omega;}}{25000};$

The equation of motion of flyback mirror 3 is under the state of big visual field:

$\mathrm{\&delta;}\left(t\right)=Z0+8.34\mathrm{\&omega;t}-\mathrm{INT}\left(6.1\mathrm{\&omega;t}\right)\frac{417\mathrm{\&omega;}}{12500};$

Above embodiment is merely representative embodiment of the present invention, but the present invention also can adopt other variant embodiment, and obtains and the essentially identical technique effect of the preferred embodiment of the present invention.For example: refrigeration mode infrared focal plane detector, non-refrigeration type infrared focal plane detector that photoelectric platform adopts; Service band is the infrared focal plane detector of shortwave, medium wave, long wave band; There is or does not exist intermediate image plane in lens combination 4; Infrared afocal system can be monoscopic, many visual fields or continuous vari-focus system, and under each visual field state, the flyback mirror carries out work according to the equation of motion of fast cycle flyback provided by the invention.

Can find out that by the foregoing description flyback mirror fast cycle of the present invention flyback makes infrared camera in whole integral time or time constant, stare Same Scene all the time, solve image blurring problem in the photoelectric platform fast rotational; The flyback mirror places the optics exit pupil position of infrared afocal system, makes its size minimum, and weight is the lightest, is convenient to servocontrol; The optics entrance pupil position of infrared afocal system is positioned on first lens combination, reduces infrared camera in the size perpendicular to optical axis direction, reduces the aperture amount aberration of optical system, dwindles its volume, reduces its cost; Flyback mirror and catoptron are turned back to light path, are convenient to the miniaturization of infrared camera.

Although be the example purpose, the preferred embodiments of the present invention are disclosed, it also is possible those skilled in the art will recognize various improvement, increase and replacement, therefore, scope of the present invention should be not limited to the foregoing description.

Claims (10)

1. an infrared optical system is characterized in that, said infrared optical system is installed on the photoelectric platform that adopts infrared focal plane detector; Said infrared optical system comprises first lens combination, second lens combination, flyback mirror and the 3rd lens combination; Wherein, said flyback mirror is between said second lens combination and the 3rd lens combination; Said first lens combination, second lens combination all have positive light coke; And the rear focus F1 of said first lens combination overlaps with the focus in object space F2 of second lens combination; Said first lens combination, second lens combination constitute infrared afocal system; Said flyback mirror is around self turning axle rotation, cycle flyback; Said infrared optical system each in integral time or time constant constantly all receives the Same Scene information that is positioned at infinity, and by said the 3rd lens combination the infrared radiation of this scene is imaged in infrared focal plane detector.

2. infrared optical system as claimed in claim 1 is characterized in that, the equation of motion of said flyback mirror cycle flyback is:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{f1}{2f2}\{{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}-\mathrm{INT}[\frac{360{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}}{n(1-\mathrm{\&beta;})}\left]\frac{{\&Integral;}_0^t\mathrm{\&omega;}\left(t\right)\mathrm{dt}}{1000}\right\};$

Wherein, the position of flyback mirror was represented with angle when δ (t) express time was t; Z0 is the zero position of flyback mirror; T is the time; F1 is the focal length of first lens combination; F2 is the focal length of second lens combination; ω (t) is the function of photoelectric platform angular velocity of rotation and time t; τ is the integral time or the time constant of infrared focal plane detector; The scene number that n needs for the spliced panoramic image; β is the scene Duplication; INT is a bracket function.

3. infrared optical system as claimed in claim 2 is characterized in that, when photoelectric platform at the uniform velocity rotated with angular velocity omega, the equation of motion of flyback mirror cycle flyback was:

$\mathrm{\&delta;}\left(t\right)=Z0+\frac{f1}{2f2}\{\mathrm{\&omega;t}-\mathrm{INT}[\frac{360\mathrm{\&omega;t}}{n(1-\mathrm{\&beta;})}\left]\frac{\text{\&omega;\&tau;}}{1000}\right\}.$

4. infrared optical system as claimed in claim 1 is characterized in that said flyback mirror is positioned at the exit pupil position of infrared afocal system, and the entrance pupil position of said infrared afocal system is positioned on said first lens combination.

5. infrared optical system as claimed in claim 1 is characterized in that, the entrance pupil position of said the 3rd lens combination overlaps with the exit pupil position of said infrared afocal system.

6. infrared optical system as claimed in claim 1 is characterized in that, there is intermediate image face in said the 3rd lens combination, or does not have intermediate image face.

7. infrared optical system as claimed in claim 1 is characterized in that, the exit pupil position of said the 3rd lens combination overlaps with the cold stop of infrared focal plane detector.

8. infrared optical system as claimed in claim 1 is characterized in that, there is the catoptron with turnover light path in said the 3rd lens combination; Said flyback mirror also is used to the light path of turning back.

9. like each described infrared optical system of claim 1～8, it is characterized in that said infrared optical system is applicable to non-refrigeration type or refrigeration mode infrared focal plane detector.

10. like each described infrared optical system of claim 1～8, it is characterized in that said infrared optical system is applicable to shortwave, medium wave or LONG WAVE INFRARED focus planardetector.

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