CN104061909A - Optical device for realizing image motion compensation based on parallel plates - Google Patents

Abstract

The invention discloses an optical device for realizing image motion compensation based on parallel plates, which comprises a pre-optical system (1), parallel plates (2), a post-optical system (3) and a focal plane component (4), wherein the emergent light paths of the pre-optical system (1) are parallel light paths or telecentric light paths; the parallel plates (2) are placed at the parallel light paths or telecentric light paths and are vertical to the optical axis; and the post-lens (3) converges and images the light paths on the focal plane component (4). In the optical device disclosed by the invention, the parallel plates are not placed at an object but behind the pre-optical system; and compared with the existing mode, the volume and weight are much less than those of a scanning reflector at the object, thus the rotational inertia of the load is smaller, and the control precision is easy to guarantee.

Description

A kind of optical devices of realizing IMC based on parallel flat

Technical field

The invention belongs to aerial camera and scout monitoring technical field, particularly a kind of aerial camera is realized the optical devices of IMC.

Background technology

Aerial camera is when to target imaging, and because camera in the time shutter and target exist relative motion, target formed picture on focal plane is not static, but varying motion, produce picture and move.Picture moves the mutual aliasing of picture that can make different target, causes image degradation, has a strong impact on image quality.At present, researcher has carried out a large amount of specialty research to IMC, find out multiple effective compensation method, such as optical image, moved penalty method, mechanical type IMC method, integrated IMC method, electronic type IMC method, digital IMC method etc.At present conventional optical profile type IMC method is to utilize the object space scanning mirror in light path to carry out IMC, and during camera exposure, object space scanning mirror is according to rotating to change radiation direction with the principle that on camera focal plane, picture speed is consistent and translational speed realizes IMC.The people such as yellow violent in Changchun Institute of Optics, Fine Mechanics and Physics, CAS, Liu Jiayan adopt the compensatory approach of scanning reflection mirror in the IMC of one piece of low profile battle array aerial camera system of (electric light and control) (2009.3) the 16th 3 phase of volume 68-74 page report, the picture that aircraft is produced moves and is compensated, it is arranged in the support frame of scanning reflection mirror assembly, around the axle rotation of vertical optical systematic optical axis.During aerial camera photograph work, there is catoptron servo system control scanning reflection mirror rate scanning on request to move with the picture that causes of front shifting movement, luffing, driftage of compensation aircraft, realize IMC.The optical profile type IMC method of above-mentioned report, because the general volume ratio of object space scanning reflection mirror is large and heavy, so the moment of inertia of scanning mechanism load is larger, control accuracy is difficult to guarantee, thereby causes the precision of IMC relatively low.

Summary of the invention

Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, provide a kind of accuracy of image motion compensation high based on parallel flat, realize the optical devices of aerial camera IMC.

Technical solution of the present invention is: a kind of optical devices of realizing IMC based on parallel flat, comprise preposition optical system, parallel flat, rearmounted optical system and focal plane component; The light path of preposition optical system outgoing is directional light or telecentric beam path; Parallel flat is positioned over parallel light path or telecentric beam path place, and vertical with optical axis; Rearmounted lens are assembled light path to be imaged on focal plane component; Described parallel flat is by parallactic angle servo-drive system and its parallactic angle direction of angle of depression servo system control and angle of depression direction.

Described preposition optical system is a plurality of arrangements of mirrors or a plurality of lens combination.

Each parameter of described parallel flat is determined according to following formula:

$D=t\sin I{(1-\frac{1-{\sin }^{2}I}{n^2-{\sin }^{2}I})}^2---\left(1\right)$

Wherein, n is refractive index, and t is thickness, and I is angle of inclination, and D is given compensate for displacement amount.

The present invention's beneficial effect is compared with prior art:

(1) the present invention arranges parallel flat after preposition optical system, and is not placed on object space, compares with current mode, and its volume and weight is far smaller than the scanning reflection mirror at object space, so the moment of inertia of its load is less, and control accuracy easily guarantees.

(2) the present invention utilizes the characteristic of parallel flat, the IMC that not only can carry out aerial camera roll direction can also be controlled the IMC that it carries out pitch orientation, has avoided control difficulty and the control accuracy problem of complete machine or the compensation of object space scanning reflection mirror.

(3) parallel flat of the present invention adopts parallactic angle and angle of depression servo system control, can be used for reducing the impact of vibration and aspect, realizes initiatively as stabilization function.

Accompanying drawing explanation

Fig. 1 is schematic diagram of the present invention;

Fig. 2 is the schematic diagram that the present invention realizes IMC.

Embodiment

Below in conjunction with accompanying drawing, the present invention is described in further detail.

As shown in Figure 1, a kind of optical devices of realizing IMC based on parallel flat of the present invention, comprise preposition optical system 1, parallel flat 2, rearmounted optical system 3 and focal plane component 4.The light path of described preposition optical system 1 outgoing is directional light or telecentric beam path, and described parallel flat 2 is positioned over parallel light path or telecentric beam path place, and vertical with optical axis; Described rearmounted lens 3 are assembled light path to be imaged on focal plane component 4; Parallel flat 2 is controlled its parallactic angle direction and angle of depression direction by parallactic angle servo-drive system 5 and angle of depression servo-drive system 6.

Described preposition optical system 1 is a plurality of arrangements of mirrors or a plurality of lens combination, for realizing the function of outgoing directional light or telecentric beam path.

Each parameter of described parallel flat 2 is determined according to following formula:

$D=t\sin I{(1-\frac{1-{\sin }^{2}I}{n^2-{\sin }^{2}I})}^2---\left(1\right)$

Wherein, n is refractive index, and t is thickness, and I is angle of inclination, and D is given compensate for displacement amount.

From formula (1), according to the compensate for displacement amount D of required compensation, only two parameters among the refractive index three of the corresponding thickness t of need confirmation parallel flat 2, inclination angle I and selection material, can obtain the 3rd parameter.The caliber size of parallel flat 2 is determined by preposition optical system 1 emergent light bore.

Described parallactic angle servo-drive system 5 and angle of depression servo-drive system 6 be for stablizing parallactic angle direction and the angle of depression direction of parallel flat 2, and in exposure, carry out the IMC of roll and pitch orientation.

Parallactic angle servo-drive system 5 is by parallactic angle driving moment motor, parallactic angle gyro, parallactic angle angular transducer and gyro the electric circuit constitute, for stablizing the parallactic angle direction of parallel flat 2, in the time of exposure, parallactic angle servo-drive system 5 control rotation parallel flats 2 carry out parallactic angle direction IMC.

Angle of depression servo-drive system 6 is comprised of angle of depression torque motor, angle of depression gyro, angle of depression gyro circuit and angle of depression angular transducer, for stablizing the angle of depression direction of parallel flat 2, in the time of exposure, servo-drive system 6 control rotation parallel flats 2 in the angle of depression carry out angle of depression direction IMC.

As shown in Figure 2, the course of work of apparatus of the present invention is: when aerial camera carries out photographic imagery to target, camera sends synchronizing pulse, speed and attitude that the responsive camera of parallactic angle and angle of depression gyro changes, the compensate for displacement amount D determining according to formula (1) and the relation between parallel flat 2 anglecs of rotation, by parallactic angle driving moment motor and angle of depression driving moment motor, contraposition angular direction and angle of depression direction are adjusted respectively, by parallactic angle angular transducer 5 and angle of depression angular transducer 6 feedbacks, form closed-loop control system respectively, parallactic angle and angle of depression make-up time are the time shutter, guarantee the image stabilization precision of aerial camera within the time shutter, after end exposure, parallel flat 2 repositions.

The maximum change amount of parallel flat 2 angular direction in place and angle of depression direction determines by the difference at Optical System Design field angle and actual field of view of receiver angle, and the size of its specific implementation parallactic angle and angle of depression change amount is controlled by parallactic angle servo-drive system 5 and angle of depression servo-drive system 6.

Certainly, to each building block of the present invention, position relationship and connected mode, in the situation that not changing its function, the equivalent transformation carrying out or alternative, also falls into protection scope of the present invention.

The present invention not detailed description is known to the skilled person technology.

Claims (3)

1. based on parallel flat, realize optical devices for IMC, it is characterized in that: comprise preposition optical system (1), parallel flat (2), rearmounted optical system (3) and focal plane component (4); The light path of described preposition optical system (1) outgoing is directional light or telecentric beam path; Described parallel flat (2) is positioned over parallel light path or telecentric beam path place, and vertical with optical axis; Described rearmounted lens (3) are assembled light path to be imaged on focal plane component (4); Described parallel flat (2) is controlled its parallactic angle direction and angle of depression direction by parallactic angle servo-drive system (5) and angle of depression servo-drive system (6).

2. according to a kind of optical devices of realizing IMC based on parallel flat of claim 1, it is characterized in that: described preposition optical system (1) is a plurality of arrangements of mirrors or a plurality of lens combination.

3. according to a kind of optical devices of realizing IMC based on parallel flat of claim 1, it is characterized in that: each parameter of described parallel flat (2) is determined according to following formula:

$D=t\sin I{(1-\frac{1-{\sin }^{2}I}{n^2-{\sin }^{2}I})}^2---\left(1\right)$

Wherein, n is refractive index, and t is thickness, and I is angle of inclination, and D is given compensate for displacement amount.