CN101373271A - Image pick-up system and method - Google Patents

Abstract

The invention discloses a photographic system including an equal-blurring intermediary image capturing device and an image processing device, wherein the equal-blurring intermediary image taking device is used for carrying out the space-invariant optical system processing to optical information of an object space and then capturing the non-conjugated equal-blurring intermediary image of an object to be tested; and the image processing device is used for processing the equal-blurring intermediary image, which includes the steps of optical-processing or digital-processing and capturing the final image of the object to be tested. The invention further discloses a photographic method. The invention realizes equal-blurring imaging of equal-blurring field depth through changing space-variant to space-invariant, then processes the image, obtains the clear final image, and improves the field depth of the imaging system.

Description

A kind of camera system and image capture method

Technical field

The present invention relates to optics and technical field of image processing, particularly relate to a kind of camera system and image capture method.

Background technology

Present optical imaging system all is to be basic fundamental with the optical focus, and the optical system of direct imaging, one of its feature are exactly that the depth of field is limited, and this just makes the imaging outside its field depth thicken, and amount of image information is abundant and sufficient inadequately.It forms reason is exactly that the imaging response of system is relevant with the object distance of object space because present optical system all is to be designed to linear space-variant system, so system changes the variation of the response of its different object distances year old object distance.

Summary of the invention

The problem that the embodiment of the invention will solve provides a kind of camera system and image capture method, because the depth of field is limited, makes the defective that imaging outside its field depth thickens to overcome in the prior art.

For achieving the above object, the technical scheme of the embodiment of the invention provides a kind of camera system, described system comprises: wait fuzzy intermediary image deriving means, be used for that the optical information to object space is carried out empty constant optical system and handle, obtain the fuzzy intermediary image such as unconjugated grade of scenery to be measured; Image processing apparatus is used for fuzzy intermediary image such as described grade is handled, and obtains the final image of described scenery to be measured.

Wherein, fuzzy intermediary image deriving means such as described grade is that afocal is taken the photograph type device far away, effective picked-up object distance that described afocal is taken the photograph type device far away satisfies the requirement of the scopes beyond greater than focal length several times according to the system design precision, realize the fuzzy imaging such as non-conjugated grade of this scope, its output face position is set in f ± Δ short before or after the accurately image planar range of design depth of field correspondence (Δ〉0) zone; It is lens class focusing system, reflection class focusing system or comprehensive catadioptric focusing system that described afocal is taken the photograph type device far away.

Wherein, fuzzy intermediary image deriving means such as described grade is a multiple-point focusing offset-type device, have a few in the design field depth in the visual field of described multiple-point focusing offset-type device is owing to the compensation of multiple-point focusing to different object distances, the point spread function psf approximately equal in the output face; Described multiple-point focusing offset-type device comprises lens class focusing system, reflection class focusing system or the comprehensive catadioptric focusing system of symmetroid.

Wherein, fuzzy intermediary image deriving means such as described grade also comprises transmitance decay mask plate, is used to enlarge the scope and the precision of the fuzzy depth of field such as described grade.

Wherein, described image processing apparatus comprises that the output face of taking the photograph type device far away with afocal is that the big F of input aperture counts optical imaging system and corresponding aberration calibration image disposal system, described big F counts first output face coincidence of taking the photograph type device far away with afocal of optical imaging system, in lens combination, its first eyeglass is a field lens; Described device is refraction class lens combination, reflection type systematic or comprehensive catadioptric system.

Wherein, described refraction class lens combination such as is at refractive index curved surface refracting medium lens and/or gradient-index lens.

Wherein, described image processing apparatus is the digital picture capturing system, and its imaging surface is positioned at etc. in the output face of fuzzy intermediary image deriving means, according to the psf of priori utilize image processing algorithm etc. fuzzy intermediary image revert to picture rich in detail.

The technical scheme of the embodiment of the invention also provides a kind of image capture method, said method comprising the steps of:

A. will carry out empty constant optical system to the optical information of object space and handle, and obtain the fuzzy intermediary image such as non-conjugated of scenery to be measured;

B. fuzzy intermediary image such as described grade is handled, obtained the final image of described scenery to be measured.

Wherein, described steps A is specially:

A1. will take the photograph type device far away by afocal at the pointolite in waiting fuzzy field depth, the fuzzy intermediary image such as grade of fuzzy characteristics such as one-tenth in short f ± Δ before or after the accurately image planar range of design depth of field correspondence (Δ〉0) zone; Or

A2. will be at the multiple-point focusing offset-type device of the pointolite in waiting fuzzy field depth by symmetroid, the fuzzy intermediary image of fuzzy characteristics such as in output face, form.

Wherein, when described steps A adopted steps A 1, described step B was specially: fuzzy intermediary image such as described grade is counted optical imaging system by big F assemble, described big F counts first output face coincidence of taking the photograph type device far away with described afocal of optical imaging system; When described steps A adopted steps A 1 or A2, described step B was specially: according to the psf of priori utilize image processing algorithm etc. fuzzy intermediary image revert to picture rich in detail, described image processing algorithm comprises that dimension receives liftering restoration methods or nonlinear method.

Compared with prior art, technical scheme of the present invention has following advantage:

The embodiment of the invention by space-variant to sky constant transformation the fuzzy imaging such as grade of the fuzzy depth of field such as realized, more described imaging is handled, obtain final image clearly, realized full focal length images picked-up.

Description of drawings

Fig. 1 is the illustrative view of functional configuration of a kind of camera system of the embodiment of the invention;

Fig. 2 is a kind of multi-focus lens focus group synoptic diagram of the embodiment of the invention;

Fig. 3 is a kind of discrete multi-focus lens synoptic diagram of the embodiment of the invention;

Fig. 4 is that a kind of little F of the embodiment of the invention counts the big F of C-IV+ and counts imaging system image optics characteristic synoptic diagram;

Fig. 5 is that the another kind of little F of the embodiment of the invention counts the big F of C-IV+ and counts imaging system image optics characteristic synoptic diagram;

Fig. 6 is a kind of truncate C-IV image field far away+with crown of roll lens imaging system figure of the embodiment of the invention;

Fig. 7 is a kind of truncate C-IV image field far away+image processing system figure of the embodiment of the invention;

Fig. 8 is the nearly image field of a kind of truncate C-IV+with axle concavees lens imaging system figure of the embodiment of the invention;

Fig. 9 is the nearly image field of a kind of truncate C-IV+image processing system figure of the embodiment of the invention;

Figure 10 is the design diagram that a kind of dual reflective mode of the embodiment of the invention forms identical psf;

Figure 11 is that a kind of co-continuous focus group delay of the embodiment of the invention is opened up formula E-IV+ Flame Image Process synoptic diagram;

Figure 12 is that a kind of co-continuous focus group delay that has amplitude formula mask plate of the embodiment of the invention is opened up formula E+IV+ Flame Image Process synoptic diagram;

Figure 13 is a kind of catoptron diverging system synoptic diagram of the embodiment of the invention;

Figure 14 is a kind of catadioptric formula catoptron collecting system synoptic diagram of the embodiment of the invention;

Figure 15 is a kind of discrete multiple-point focusing bucking-out system lens-shape figure of the embodiment of the invention;

Figure 16 is a kind of continuous multiple-point focusing bucking-out system lens-shape figure of the embodiment of the invention.

Embodiment

Below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail.Following examples are used to illustrate the present invention, but are not used for limiting the scope of the invention.

Following notion has been proposed among the present invention:

The fuzzy depth of field: with respect to the notion of the depth of field of blur-free imaging, the fuzzy depth of field is meant the pointolite for object space, can obtain the object distance scope of non-point-like psf in the image space, in whole object distance scope and clear depth of field complementation.

Etc. the fuzzy depth of field: the pointolite in the fuzzy depth of field is at the approximately equalised fuzzy field depth of the psf of image planes.

V (viarable): traditional optical imaging system all is burnt interior imaging, realizes the space-variant optical information processing for the optical information of object space, is the space-variant optical system, is output as the image of clear and fuzzy coexistence.

IV (inviarable): empty invariant system, the fuzzy intermediary image capturing apparatus of grade of the present invention is realized the optical information of object space such as is carried out at Fuzzy Processing by the compensation of afocal imaging or multiple-point focusing, be converted to the sky invariant system the space-variant system is approximate, blurred picture such as be output as.

C-IV is meant the empty invariant system of truncate formula, or fuzzy system such as truncate formula.

The output face of C-IV: the output face that afocal is taken the photograph the fuzzy depth of field of grade far away system is outside the blur-free imaging point range of target field depth correspondence, promptly outside the focusing range.

E-IV is meant the empty invariant system of continuation formula, or fuzzy system such as continuation formula.

The output face of E-IV: the output face of depth of field systems such as multiple-point focusing compensation is the center of these many focuses, depends primarily on the focus of its place optical system.

The input face of the big long depth of focus of F number system: this input face is exactly the input aperture of this optical system, is exactly the front surface of field lens in lens combination, is exactly reflecting surface in reflecting system.In the combination of C-IV and the big long depth of focus of F number system was implemented, the input face of the output face of C-IV and the big long depth of focus of F number system overlapped.

The present invention is based on that the imageable target of full focal length studies, in order to realize the target of this full focal length imaging, proposed fuzzy imaging such as non-conjugated grade and etc. the fuzzy depth of field notion and the method that the fuzzy depth of field realizes such as invented, be C-IV (truncate formula sky is constant) and E-IV (continuation formula sky is constant) method, the C-IV method is exactly that afocal is taken the photograph application far away, the picked-up object distance scope of system is outside focal range, and outgoing position to be imaging surface before and after the focus of image space very near but the position, thereby fuzzy empty constant photographic such as realization; And the E-IV method is to realize the focus-compensating of full focal length photography with many focuses group method of focusing, the present invention has provided method for designing and the face type equation of realizing the multiple-point focusing offset lens of E-IV, according to fuzzy psf outputs such as lens of inventing or optical device just can obtain.After fuzzy intermediary image capturing apparatus such as having realized, its output there are two kinds of disposal routes, for the output of C-IV and E-IV, directly obtain waiting fuzzy vague image, it is carried out Digital Image Processing, using same psf recovers original image; For the output of C-IV, invented with field lens and gone imaging as the long depth of focus of the big F number system of first mirror, so just utilize the finite resolving power demand of system imaging and long depth of focus characteristic the error of the fuzzy depth of field such as to offset, realized full focal length images picked-up, the big F combined method of this little F is full focal length realization fully photographically.The design that the present invention has also proved the good optical characteristics of the big F combined method of little F theoretically realizes direction.

The illustrative view of functional configuration of a kind of camera system of the embodiment of the invention fuzzy intermediary image deriving means and image processing apparatus such as comprises as shown in Figure 1.Fuzzy intermediary image deriving means such as described grade is used for the optical information to object space is carried out being that the constant optical system of sky handles, and obtains the fuzzy intermediary image such as non-conjugated of scenery to be measured; Described image processing apparatus is used for fuzzy intermediary image such as described grade is handled, and obtains the final image of described scenery to be measured.Fuzzy intermediary image deriving means such as described grade comprises that afocal takes the photograph type device far away or multiple-point focusing offset-type device; Described image processing apparatus comprises that big F counts optical imaging system and corresponding aberration calibration image disposal system, or digital image processing system.

Afocal is taken the photograph type device characteristic far away:

It is lens class focusing system, reflection class focusing system or the comprehensive catadioptric focusing system that the aperture is big, focal length is short that described afocal is taken the photograph type device far away; It effectively absorbs object distance according to the satisfied requirement greater than several times of scopes in addition of focal length of system design precision, realize the fuzzy depth of field such as grade of this scope, its output face position is set in f ± Δ short before or after the accurately image planar range of design depth of field correspondence (Δ〉0) zone.The fuzzy greatly field depth characteristic of its little clear depth of field with the short focal length telephoto lens of little F number transforms to the what comes into a driver's in fuzzy field depth of object distance in the visual field before or after the rear focus, obtains approximate consistent intermediary image of psf or approximate consistent COMPLEX AMPLITUDE; Little F counts imaging lens can realize the big fuzzy depth of field such as grade more.Can add that the transmissivity pupil function improves approximation quality, the fuzzy depth of field such as expansion, and improve transmitance.The short afocal telephoto lens of little F number includes but not limited to that the refraction type afocal takes the photograph lens far away, reflective afocal telephoto lens, afocal and take the photograph catadioptric camera lens far away, diffraction condenser lens (becoming transmissivity pupil function diffraction condenser lens).

Utilize low beam to learn the depth of field weak point of system, near, and fuzzy depth of field length and basically identical has complementary characteristics with the depth of field, so it also is fuzzy intermediary image capturing apparatus such as truncate type that the short afocal of little F number is taken the photograph fuzzy intermediary image capturing apparatus such as formula far away, C-IV perhaps makes afocal take the photograph the fuzzy intermediary image capturing apparatus of grade far away.

C-IV realizes principle:

If blur radius is the imaging of R, (establishing object distance is U, and at a distance of being v, the focal length of lens is f, and the distance between lens and light-sensitive surface is when being D in the aperture

The aperture is D), have:

In the f+ pattern: promptly

Here

M is the multiple of object distance with respect to focal length,

Be a constant, then error is

When m was very big, blur radius was a constant.

In the f-pattern:

No matter be f+ pattern or f-pattern, R is at m " 1 o'clock, level off to blur radius such as constant, formation.The degree of accuracy of R depend on m and

The precision of the fuzzy depth of field such as grade during system design and image restoration precision depend on m and

In the time of fixedly, so improve the m number, be the striving direction that improves the blur level precision, compression f value is the striving direction of the fuzzy depth of field such as raising.

Take the photograph apotype at this afocal, as long as the system that ordinary lens is formed U " f, the scope of the fuzzy depth of field such as be exactly, the what comes into a driver's of this scope can only be realized fuzzy imaging such as non-conjugated grade in image planes.

For reflection or catadioptric formula focusing system, same imaging mechanism is arranged, so at U " during f, the radius of the confuson disc of its imaging is exactly the same diameter, the fuzzy depth of field such as has.

So compress the f value, the scope of the fuzzy depth of field such as also just enlarged as far as possible.Reduce the picture quality requirement, reduce the system design precision, the scope of the fuzzy depth of field such as also improved.

Because taking the photograph the distance imaging system with afocal all has symmetry, so COMPLEX AMPLITUDE on its imaging surface or psf confuson disc also are symmetrical when not considering aberration.

E-IV realizes principle:

Described multiple-point focusing offset-type device comprises lens class focusing system, reflection class focusing system or the comprehensive catadioptric focusing system of symmetroid, its in the visual field, design in the field depth have a few since multiple-point focusing to the compensation of different object distances, the point spread function psf approximately equal in the output face.For the fuzzy intermediary image such as grade that obtains, carry out image with the method for Digital Image Processing and recover, obtain designing the full focal length what comes into a driver's imaging in the object distance scope; Can add that the transmissivity pupil function improves approximation quality.The multiple-point focusing bucking-out system includes but not limited to symmetrical multiple-point focusing bucking-out system, comprises symmetrical multiple-point focusing bucking-out system, catadioptric combination symmetry multiple-point focusing bucking-out system.

The characteristics of the complementary lens of multiple-point focusing are:

The one side that is characterized as in the two sides of lens is single focus focusing surface, and another side is the multiple-point focusing face, perhaps meets the optical system of the equivalent light path of above two sides technological synthesis feature, comprises the principle of reflection light path, as shown in Figures 2 and 3.The multiple-point focusing face meets following feature:

1. the focus group is divided into two, realizes the mutual compensation of far and near object distance;

2. two focus groups are by one group two or organize two complementary curved surfaces more and form, and every group of complementary curved surfaces constitutes and focus on complementaryly, realizes the point spread function approximately equal of different object distances correspondence on image planes;

3. the focus group can be continuous focus group and discrete focus group;

4. the focus group is realized by continuous complementary curved surfaces continuously; Discrete focus group is realized by the complementary curved surfaces that the convex-concave sphere with different focal at diverse location place, distance lens center constitutes;

5. no matter be continuous focus group or discrete focus group, by nearly over focus group order, the corresponding relation of the size of lens radius/focus distance can be divided into four classes: long radius perifocus-long radius perifocus, long radius perifocus-long radius over focus, long radius over focus-long radius perifocus, long radius over focus-long radius over focus, present embodiment is long radius perifocus-long radius over focus combination, the radius here is meant the radius under circle pupil situation, if Fang Tong, then refer to the distance of lens face apart from central point, here be with the lens explanation, in like manner can be corresponding to reflecting system, catadioptric system;

6. inside and outside (distance) focus groups of two complementary curved surfaces, light transmission capacity identical;

7. focus group's curved surface formation meets following principle continuously:

7.1. lens curved surface can be the rotational symmetry system, also can be the center balanced system.The function expression z of rotational symmetry system usefulness separable geometries (x, y)=z (y) * z (x) expression, z is that optical axis is a coordinate axis, x, y are respectively mutually perpendicular two axles in addition perpendicular to optical axis; The center balanced system can by the function expression z of separable geometries (r, theta)=z (r) * z (theta) expression, z is that optical axis is a coordinate axis, r is the outside direction of polar coordinates radius, theta is the polar coordinates sense of rotation.

7.2. above z (x), the structure of z (r) meets following steps:

7.3. be provided with the continuous non-once odd function z in n bar normalization space _i(x) (1,1) and about the symmetric function z of x=0 _i(-x) (1,1), promptly

z _i(x) -1≤x≤1，1≤i≤n.

z _i(-x) -1≤x≤1，1≤i≤n’

7.4. each z _i(x) 1≤i≤n is divided into positive and negative two sections

z _i(x)[u(x)-u(x-x _i，0)] -1≤x≤1 1≤i≤n 0≤x _i，0≤1

z _i(x)[u(x+x _i，0)-u(x)] -1≤x≤1 1≤i≤n 0≤x _i，0≤1

z _i(-x)[u(x)-u(x-x _i，0)]?-1≤x≤1 1≤i≤n 0≤x _i，0≤1

z _i(-x)[u(x)-u(x-x _i，0)]?-1≤x≤1 1≤i≤n 0≤x _i，0≤1

7.5. carry out identical intercepting to two sections

z _i(x)[u(x-x _i，s)-u(x-x _i，b)] -1≤x≤1 1≤i≤n 0≤x _i，s≤x _i，b≤1

z _i(x)[u(x+x _i，b)-u(x+x _i，s)] -1≤x≤1 1≤i≤n 0≤x _i，s≤x _i，b≤1

z _i(-x)[u(x-x _i，s)-u(x-x _i，b)] -1≤x≤1 1≤i≤n 0≤x _i，s≤x _i，b≤1

z _i(-x)[u(x+x _i，b)-u(x+x _i，s)] -1≤x≤1 1≤i≤n 0≤x _i，s≤x _i，b≤1

Connect combination 7.6. carry out displacement, four sections symmetries are formed two sections of symmetries, it is right to obtain the symmetrical complement curve

$z_i(x-\frac{x_{i,c}}{2})[u(x-x_{i,s}-\frac{x_{i,c}}{2})-u(x-x_{i,b}-\frac{x_{i,c}}{2})]+z_i(-x-\frac{x_{i,c}}{2})[u(x-x_{i,s}+\frac{x_{i,c}}{2})-u(x-x_{i,b}+\frac{x_{i,c}}{2})]$

$z_i(-x-\frac{x_{i,c}}{2})[u(x+x_{i,b}+\frac{x_{i,c}}{2})-u(x+x_{i,s}+\frac{x_{i,c}}{2})]+z_i(x-\frac{x_{i,c}}{2})[u(x+x_{i,b}-\frac{x_{i,c}}{2})-u(x+x_{i,s}-\frac{x_{i,c}}{2})]$

-1≤x≤1 1≤i≤n 0≤x _i，s≤x _i，b≤1 0≤x _i，c≤1

7.7. carry out equal proportion yardstick, amplitude conversion, obtain

$\stackrel{\‾}{z_i\left(x\right)}=k_i{z}_i\left(\frac{x-\frac{x_{i,c}}{2}}{s_i}\right)[u\left(\frac{x-x_{i,s}-\frac{x_{i,c}}{2}}{s_i}\right)-u\left(\frac{x-x_{i,b}-\frac{x_{i,c}}{2}}{s_i}\right)]+k_i{z}_i\left(\frac{-x-\frac{x_{i,c}}{2}}{s_i}\right)[u\left(\frac{x-x_{i,s}+\frac{x_{i,c}}{2}}{s_i}\right)-u\left(\frac{x-x_{i,b}+\frac{x_{i,c}}{2}}{s_i}\right)]$

$\stackrel{\‾}{z_i(-x)}=k_i{z}_i\left(\frac{-x-\frac{x_{i,c}}{2}}{s_i}\right)[u\left(\frac{x+x_{i,b}+\frac{x_{i,c}}{2}}{s_i}\right)-u\left(\frac{x+x_{i,s}+\frac{x_{i,c}}{2}}{s_i}\right)]+k_i{z}_i\left(\frac{x-\frac{x_{i,c}}{2}}{s_i}\right)[u\left(\frac{x+x_{i,b}-\frac{x_{i,c}}{2}}{s_i}\right)-u\left(\frac{x+x_{i,s}-\frac{x_{i,c}}{2}}{s_i}\right)]$

k _iBe amplitude conversion coefficient, arithmetic number, s _iBe the change of scale coefficient, be arithmetic number ,-1≤x≤1 1≤i≤n

0≤x _i，s≤x _i，b≤1 0≤x _i，c≤1

7.8. carry out identical along x, the z displacement and and carried out complementary segment of curve that same step obtains and be connected and constitute space normalization symmetric focused complementation curve z (x) x that multistage makes up in (1,1), perhaps z (r) r is in (0,1);

7.9. obtain z (y) y equally in (1,1), further obtain the complementary lens curved surface z of rotational symmetry multiple-point focusing (x, y)=z (x) * z (y).

7.10. the complementary lens curved surface z of the symmetrical multiple-point focusing in the center of constructing similarly (r, theta)=z (r) * z (theta), wherein z (theta)=z (pie-theta) and z (theta) they are theta continuous function in the 2pie scope.

8. discrete focus group's curved surface formation meets following principle:

8.1. this curved surface can also can be the many focus systems of center symmetry for the many focus systems of axisymmetric curved surface, the function expression z of rotational symmetry system usefulness separable geometries (x, y)=z (y) * z (x) expression, z is that optical axis is a coordinate axis, x, y are respectively mutually perpendicular two axles in addition perpendicular to optical axis; The center balanced system can by the function expression z of separable geometries (r, theta)=z (r) * z (theta) expression, z is that optical axis is a coordinate axis, r is the outside direction of polar coordinates radius, theta is the polar coordinates sense of rotation.

8.2. above z (x), the structure of z (r) meets following steps:

8.3.z _i(x) can have positive negative focal length for two interconnected one protruding concave arcs, be respectively nearly over focus group's a focus, has the focusing complementation, is that a complementary focusing is right.

8.4.z _i(x) also can for the combination of a plurality of male and female faces obtain one group complementary focus on right.

8.5. many complementary focusing constitute the curve z (x) that convex-concave is alternate to being connected, and obtain positive and negative focus group, act on mutually with another single focus, obtain far and near two and focus on complementary focus group.

8.6. the same manner obtains z (y), and then (x y)=z (x) * z (y), obtains rotational symmetry and focuses on complementary lens curved surface to obtain z.

8.7. the same manner obtains z (r), and then (r theta)=z (r) * z (theta), obtains the complementary lens curved surface of center symmetric focused to obtain z.Wherein z (theta)=z (pie-theta) and z (theta) are theta continuous function in the 2pie scope.

Multiple-point focusing complementary optical system (many focuses refraction class lens and reflection class turn back mirror or its in conjunction with), this is the way of the fuzzy depth of field such as structure, the target of structure is that the depth of field is strengthened, and will blur inevitably simultaneously, but what pursue the fuzzy depth of field or the fuzzy depth of field such as approximate such as is.

The lens that can be plane of symmetry type also can be the lens of non-plane of symmetry type.Can go by curved surface to realize, also can go to realize, also can go to realize in conjunction with curved surface by the graded index medium by graded index medium gradual change media plate with medium.

Transmitance decay mask plate:

Fuzzy intermediary image deriving means such as described grade also comprises transmitance decay mask plate, is used to enlarge the scope and the precision of the fuzzy depth of field such as described grade, the logical light quantity of regulation and control simultaneously.The transmitance shutter is a modulation to the frequency spectrum of imaging, and this modulation is correlated with according to the transmitance toroidal function.We in this invention the inside the transmitance shutter as of the prolongation of an option as fuzzy depth of field such as realizations.Transmitance decay mask plate as embodiment is:

A. Gauss's transmissivity: the transmitance curved surface of shutter is Gauss's curved surface regularity of distribution, transmitance $T(x,y)=K{e}^{-\frac{x^2+{\mathrm{<figure-callout\; id="2"\; label="y"\; filenames="A200810118437E00241.png,A200810118437E00242.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{{\mathrm{\&sigma;}}^2}},$ K is a normalization coefficient, and σ is the curved surface variance.

B. negative exponent transmissivity: the transmitance curved surface of shutter is the negative exponent curved surface regularity of distribution, and transmitance T (x, y)=Ke ^{-a (| x|+|y|)}, K is a normalization coefficient, a is the curved surface attenuation coefficient.

C. other transmissivity curved surfaces: the continuation of the fuzzy depth of field of transmitance curved surface equity of edge decay all has effect.Such as conical camber etc.Also comprise nonconcentric(al) amplitude transmissivity curved surface.

The optical imagery treating apparatus: big F counts optical imaging system.

Described big F counts that the absolute value of F number of optical imaging system is relatively large, depth of focus is longer, first output face coincidence of taking the photograph type device far away of its system with afocal, in lens combination, its first eyeglass is a field lens, and these characteristics have determined the low-pass filtering that diffraction effect caused that this imaging system does not have pupil to bring.Among the present invention, refractive index curved surface refracting medium lens and/or gradient-index lens such as the general employing of described refraction class lens combination.

Leave in the certain scope of imaging point (focus), the hot spot of the output of empty invariant system is handled made it to defocus or focus on the imaging screen setting up a cover imaging system before or after the focus point, this imaging system is that a big F counts imaging system, this lens imaging system is near focus or imaging point, the spot radius of light that empty invariant system is radiated the imaging len surface is very little, the radiation direction of each picture point is approximate always, shape is taper once, after the imaging system output of excessive F number, its light beam is the very little focusing light cone of very narrow angle, has very big depth of focus.This imaging system does not all have the diffraction by aperture effect for every Shu Guang, because incide the only very narrow light beam on the lens.Be arranged on the difference of front and back of the position of focus according to first lens surface of imaging system, then imaging system can be focusing system (positive system) or defocused system (negative system).The lens surface of positive system is after focus point, and the surface of negative system is before focus point.For approximate each consistent imaging beam, because its light beam that incides the imaging len surface is very narrow, the F number of lens is very big, then its outgoing beam is then very narrow, focus point is far away relatively, depth of focus is bigger, because the Pixel Dimensions of imaging screen has determined the depth of focus of imaging, be designed to the picture lens combination, make the depth of focus of its all light beams that common position or zone can both be arranged, select in this position or the zone a bit as imaging screen, so then obtain focal imaging for the light source of object space in fuzzy big field depth.This system comprises following four main points: 1. afocal is taken the photograph system far away and is obtained the big fuzzy depth of field; 2. big F number system obtains big imaging depth of focus, is divided into negative positive lens imaging system according to the front and back that are arranged on focus; 3. according to the system accuracy requirement, big F counts the lens surface of imaging system by the focus (also can be focus point) of taking the photograph system far away in various degree near afocal; 4. according to full focal range requirement, the imaging resolution requirement of system, a plurality of space-variants can be set changes empty invariant system, and the full focal length optical imaging system that satisfies above three main points is designed in overall equilbrium in engineering design.

Big F counts imaging system design main points:

Common feature: big F number, focus on the class field lens preceding, long depth of focus evenly distributes.

1. no matter field lens is convex lens or concavees lens, and its aperture of inciding the light of big F number system all is less, the smaller the better, and the light cone angle of its outgoing is just very little like this, and last depth of focus is just very long.But the aperture that wants incident light here is more little, and the blur level of the fuzzy depth of field such as grade of correspondence such as fuzzy intermediary image capturing apparatus such as its grade is accurate more, waits fuzzy field depth more little.

Since etc. fuzzy intermediary image capturing apparatus be that extra small F counts afocal and takes the photograph system far away, its emerging beam cone angle very big (can certainly transfer lessly) so, and the distance that arrives at lens point is shorter, and the refractive index of system will be tried one's best greatly like this, and this will carry out equilibrium and weigh in specific design.

3. convex lens condenser system, the f+ system, the refractive index situation that the plane of incidence will be counted imaging system according to the accuracy requirement and the big F of system, etc. the bright dipping light cone angle of fuzzy intermediary image capturing apparatus mutually equilibrium go design, the focal distance f of fuzzy intermediary image capturing apparatus such as approaching more grade, then wait fuzzy depth of field precision high more, but etc. the fuzzy depth of field more little.This system will have inverted image twice.

4. concavees lens diverging system, the f-system, the plane of incidence will be according to the accuracy requirement of system and the refractive index situation of big F imaging system, etc. the bright dipping light cone angle of fuzzy intermediary image capturing apparatus mutually equilibrium go design, the f of fuzzy intermediary image capturing apparatus such as approaching more grade, then depth of field precision is high more, but the depth of field is more little.

The digital picture capturing system:

Described image processing apparatus is the digital picture capturing system, and its photoelectric sensing imaging surface is positioned at etc. in the output face of fuzzy intermediary image deriving means, according to the psf of priori utilize image processing algorithm etc. fuzzy intermediary image imaging revert to picture rich in detail.Described image processing algorithm comprises that dimension receives liftering restoration methods or nonlinear method etc.In waiting fuzzy intermediary image capturing apparatus, its psf is consistent in waiting fuzzy field depth, and this is the core value of fuzzy intermediary image capturing apparatus.So in the visual field, the clear degree of falling of the scenery in the fuzzy depth of field is consistent or approximate consistent, and this just just lays the basis for easy degree that the image of back recovers.For the disposal route of coloured image, coloured image is resolved into each chrominance component, such as RGB, synthesize the coloured image after promptly obtaining handling after then RGB being handled respectively.

A kind of image capture method of the embodiment of the invention may further comprise the steps:

A. will carry out empty constant optical system to the optical information of object space and handle, and obtain the fuzzy intermediary image such as non-conjugated of scenery to be measured.When adopting C-IV, described steps A is specially: afocal big by the aperture at the pointolite in waiting fuzzy field depth, that focal length is short will be taken the photograph type device far away, imaging in short f ± Δ before or after the accurately image planar range of design depth of field correspondence (Δ〉0) zone.When adopting E-IV, described steps A is specially: will form the approximately equalised picture of psf in output face at the pointolite in waiting fuzzy field depth by the multiple-point focusing compensation system.

B. fuzzy intermediary image such as described grade is handled, obtained the final image of described scenery to be measured.When adopting C-IV, described step B is specially: fuzzy intermediary image such as described grade is counted optical imaging system by big F assemble, described big F counts that the absolute value of F number of optical imaging system is relatively large, depth of focus is longer, and the output face that first of its system and described afocal are taken the photograph type device far away overlaps.When adopting C-IV or E-IV, described step B is specially: according to the psf of priori with utilize image processing algorithm, etc. fuzzy intermediary image imaging revert to picture rich in detail, described image processing algorithm comprises that dimension receives liftering restoration methods or nonlinear method.

Fuzzy intermediary image capturing apparatus such as a kind of little F number of the embodiment of the invention are counted imaging system image optics characteristic synoptic diagram as shown in Figure 4 and Figure 5 with big F.With reference to Fig. 4, suppose that outside several times of f of object space, the coordinate that P is ordered is (x ₀, 0) and amplitude is unit 1.

Lens a front surface (x _a, y _a, that u) locates has an o (x _o, y _o), scioptics a is at v _aThere is i at the place _a, its psf is h at lens b front surface _A@b, at v _aLocating its psf is h _aWith Fang Tong is that example is analyzed:

$=\frac{D_a}{2}(\frac{1}{n}-\frac{1}{m}-\frac{1}{\mathrm{mn}})=\frac{D_a}{2}(\frac{m-n-1}{\mathrm{mn}}=C(m,n))=\frac{1}{2}{D}_{a}C(m,n)$

$h_{a@b}(x_a,y_a;x_o,y_o)=\mathrm{rect}\left(\frac{x_a-(M=\frac{v_a}{u_a}=\frac{1}{m-1})x_o}{2r_{a@b}}\right)\mathrm{rect}\left(\frac{y_a-\frac{1}{m-1}{y}_o}{2r_{a@b}}\right)$

$=\mathrm{rect}\left(\frac{x_a-\frac{1}{m-1}{x}_o}{D_{a}C(m,n)}\right)\mathrm{rect}\left(\frac{y_a-\frac{1}{m-1}{y}_o}{D_{a}C(m,n)}\right)$

The a lens at the picture of b lens front surface are

$i_{a@b}(x_a,y_a)=o(x_o,y_o)*h_a(x_a,y_a;x_o,y_o)=o(x_o,y_o)*\mathrm{rect}\left(\frac{x_a-\frac{1}{m-1}{x}_o}{D_{a}C(m,n)}\right)\mathrm{rect}\left(\frac{y_a-\frac{1}{m-1}{y}_o}{D_{a}C(m,n)}\right)$

When n=0, promptly R approximates 0, at v _aThe place is a conjugation diffraction spot i _a(x _a, y _a), be the Fourier transform of rectXrect, the diffraction spot of a sincXsinc function, for b lens and screen S, this diffraction spot is exactly the input light source o of b lens combination _b(x _b, y _b), it apart from the b lens is

$h_a(x_a,y_a;x_o,y_o)=\frac{D_a^2}{4}\sin c\left(\frac{D_a(x_a-\frac{1}{m-1}{x}_o)}{2\mathrm{\&lambda;}{f}_a}\right)\sin c\left(\frac{D_a(y_a-\frac{1}{m-1}{y}_o)}{2\mathrm{\&lambda;}{f}_a}\right)$

i _a(x _a，y _a)＝o _b(x _b，y _b)＝o(x _o，y _o)*h _a(x _a，y _a；x _o，y _o)

The b lens are to o _b(x _b, y _b) carry out Fourier transform and propagate into screen S imaging obtaining i _b(x _b, y _b), be not have diffraction that pupil causes, i.e. h in this conversion _b(x _b, y _bx _a, y _a) can only be at most that falling of bringing of aberration is clear, and falling of not having that diffraction brings is clear.

$r_b=\frac{D_{a}C(m,n)(S-v_b)}{2v_b}=\frac{D_{a}C(m,n)}{2}(\frac{S}{v_b}-1)=\frac{D_{a}C(m,n)}{2}(\frac{S}{f_b}-\frac{S}{u_b=d-v_a}-1)$

$=\frac{D_{a}C(m,n)}{2}(\frac{S}{f_b}-\frac{S}{f_a+\mathrm{\&Delta;}-\frac{{\mathrm{mf}}_a^2}{{\mathrm{mf}}_a-f_a}}-1)=\frac{D_{a}C(m,n)}{2}(\frac{S}{f_b}-\frac{S}{f_a+\mathrm{\&Delta;}-\frac{{\mathrm{mf}}_a}{m-1}}-1)$

$=\frac{D_{a}C(m,n)}{2}(\frac{S}{f_b}-\frac{S(m-1)}{f_a(m-1)+\mathrm{\&Delta;}(m-1)-{\mathrm{mf}}_a}-1)=\frac{D_{a}C(m,n)}{2}(\frac{S}{f_b}-\frac{S(m-1)}{\frac{f_a}{n}(m-1)-f_a}-1)$

$=\frac{D_a}{2}(\frac{S}{f_b}-\frac{S(m-1)n}{(m-n-1)f_a}-1)\frac{m-n-1}{2\mathrm{mn}}=\frac{D_a}{2}(\frac{(S={\mathrm{kf}}_b)}{f_b}C(m,n)-\frac{S(m-1)}{2{\mathrm{mf}}_a}-C(m,n))$

$=\frac{D_a}{2}(\mathrm{kC}(m,n)-\frac{k(f_b={\mathrm{lf}}_a)(m-1)}{2{\mathrm{mf}}_a}-C(m,n))=\frac{D_a}{2}(\mathrm{kC}(m,n)-\frac{\mathrm{kl}(m-1)}{2m}-C(m,n))$

$=\frac{D_a}{2}(k\frac{m-n-1}{2\mathrm{mn}}-\frac{\mathrm{kl}(m-1)\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="A200810118437E00241.png,A200810118437E00242.png"\; state="\{\{state\}\}">n</figure-callout>}}{2\mathrm{mn}}-\frac{m-n-1}{2\mathrm{mn}})=\frac{D_a}{2}(\frac{\mathrm{mk}-\mathrm{nk}-\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="A200810118437E00241.png,A200810118437E00242.png"\; state="\{\{state\}\}">k</figure-callout>}}{2\mathrm{mn}}-\frac{\mathrm{klmn}-\mathrm{<figure-callout\; id="2"\; label="k\; ln"\; filenames="A200810118437E00241.png,A200810118437E00242.png"\; state="\{\{state\}\}">k</figure-callout>}\ln }{2\mathrm{mn}}-\frac{m-n-1}{2\mathrm{mn}})$

$=D_a(\frac{\mathrm{mk}-\mathrm{nk}-k-\mathrm{klmn}+k\ln -m+n+1}{4\mathrm{mn}}=C(m,n,k,l))=D_{a}C(m,n,k,l)$

$=D_a(\frac{k}{4n}-\frac{k}{4m}-\frac{k}{4\mathrm{mn}}-\frac{\mathrm{kl}}{4}+\frac{\mathrm{kl}}{4m}-\frac{1}{4n}+\frac{1}{4m}+\frac{1}{4\mathrm{mn}})$

$=D_a(\frac{k}{4n}-\frac{\mathrm{kl}}{4}-\frac{1}{4n}+\frac{1}{4m}+\frac{1}{4\mathrm{mn}}-\frac{k}{4m}-\frac{k}{4\mathrm{mn}}+\frac{\mathrm{kl}}{4m})$

$=D_a(\frac{k-1}{4n}-\frac{\mathrm{kl}}{4}-\frac{k-1}{4m}-\frac{k-1}{4\mathrm{mn}}+\frac{\mathrm{kl}}{4m})=D_a(\frac{k-1}{4n}-\frac{\mathrm{kl}}{4}\frac{m-1}{m}-\frac{k-1}{4m}\frac{n-1}{n})$

Explanation is when m is big, as long as the aberration in the visual field is less, and f _a, f _bConsistance is very strong, on image planes S similarly be consistent and object distance it doesn't matter, thereby realize that space-variant is converted to the sky invariant system, realize full focal length; As long as k, l, n chooses, and just can find suitable m ultimate value and rational error, just can find enough big depth of focus.

$i(x_b,y_b)=o_b(x_b,y_b)*h_b(x_b,y_b;x_a,y_a)=o(x_o,y_o)*h_a(x_a,y_a;x_o,y_o)*h_b(x_b,y_b;x_a,y_a)$

$=o(x_o,y_o)*\frac{D_a^2}{4}\sin c\left(\frac{D_a{x}_a}{2\mathrm{\&lambda;}{f}_a}\right)\sin c\left(\frac{D_a{y}_a}{2\mathrm{\&lambda;}{f}_a}\right)*\mathrm{rect}\left(\frac{x_b-{\mathrm{Nx}}_a}{D_{a}C(m,n,k,l)}\right)\mathrm{rect}\left(\frac{y_b-{\mathrm{Ny}}_a}{D_{a}C(m,n,k,l)}\right)$

N is the amplification coefficient that big F counts imaging system.

With reference to Fig. 3, wherein

$i(x_b,y_b)=o_b(x_b,y_b)*h_b(x_b,y_b;x_a,y_a)=o(x_o,y_o)*h_a(x_a,y_a;x_o,y_o)*h_b(x_b,y_b;x_a,y_a)$

$=o(x_o,y_o)*\frac{D_a^2}{4}\sin c\left(\frac{D_a{x}_a}{2\mathrm{\&lambda;}{f}_a}\right)\sin c\left(\frac{D_a{y}_a}{2\mathrm{\&lambda;}{f}_a}\right)*\mathrm{rect}\left(\frac{x_b-{\mathrm{Nx}}_a}{D_{a}C(m,n,k,l)}\right)\mathrm{rect}\left(\frac{y_b-{\mathrm{Ny}}_a}{D_{a}C(m,n,k,l)}\right)$

Choosing suitable D _a, f _a, k, l is during n, promptly such as D _a=f _a, n=10, l=3, then k=1/29 so just can guarantee $\frac{D_a^2}{4}\sin c\left(\frac{D_a{x}_a}{2\mathrm{\&lambda;}{f}_a}\right)\sin c\left(\frac{D_a{y}_a}{2\mathrm{\&lambda;}{f}_a}\right)$ Be approximately δ (x _a, y _ax _o, y _o), $\mathrm{rect}\left(\frac{x_b}{D_{a}C(m,n,k,l)}\right)\mathrm{rect}\left(\frac{y_b}{D_{a}C(m,n,k,l)}\right)$ Be approximately δ (x _b, y _bx _a, y _a), so just can obtain wideband, do not have (little) and fall clear full focal length i (x _b, y _b).

The specific implementation of the embodiment of the invention such as Fig. 6～shown in Figure 16.With reference to Fig. 6, wherein, for L1, the pointolite in the visual field of effectively photographing all is the approximate fuzzy hot spot that waits by the projection of transmitance toroidal function on L2; For L2, receive blur level hot spots such as intermediary image from L1, all be a point (depth of focus is bigger) by the imaging of L2 on detector screen S; S is image planes.With reference to Fig. 7, wherein, for L1, its pointolite projection on S in the visual field of effectively photographing all is the hot spot of Approximate Equivalent; S is image planes, and the psf approximately equal in precision that receives on it is used software rejuvenation.With reference to Fig. 8, its advantage is: volume is less relatively, the depth of field big (can consider at L1, place organic glass medium between the L2, reduce refringence, improve as square focal length).Wherein, for L1, its pointolite projection on L2 in the visual field of effectively photographing all is the hot spot of Approximate Equivalent; For L2, receive blur level hot spots such as intermediary image from L1, all be a point (big depth of focus) by the imaging of L2 on detector screen S; S is image planes, and L2 and S can merge into S, and the function of L2 realizes by recovering software then.With reference to Fig. 9, wherein, for L1, its pointolite projection on S in the visual field of effectively photographing all is the hot spot of Approximate Equivalent; S is image planes, and the psf approximately equal in precision that receives on it is used software rejuvenation.With reference to Figure 10, wherein, for R1, the R2 combination, the microspur reflecting surface, consistent in accuracy rating the psf that the light of each object distance light source point reflexes on the S screen; S is image planes, and the psf approximately equal in precision that receives on it is used software rejuvenation.For the imaging system of truncate formula C-IV and big F system, can go to realize with any combination of lens and catoptron; For the imaging system of truncate formula C-IV and image processing system, can go the constant conversion of fuzzy sky such as realization with lens or catoptron.With reference to Figure 11, wherein, for continuous punktal lens, its pointolite projection on S in the visual field of effectively photographing is because the zoom complementation all is the hot spot of Approximate Equivalent; S is image planes, and the psf approximately equal in precision that receives on it is used software rejuvenation.With reference to Figure 12, wherein, for L1, its pointolite projection on S in the visual field of effectively photographing all is the approximate focus point; S is image planes.With reference to Figure 13, wherein, for L1, its pointolite projection on L2 in the visual field of effectively photographing all is the radiation of Approximate Equivalent; For M2, receive from L1 etc. the blur level rayed, all be a point (big depth of focus) by the M2 imaging of system on image planes S of turning back; S is image planes.With reference to Figure 14, wherein, for L1, its pointolite projection on L2 in the visual field of effectively photographing all is the radiation of Approximate Equivalent; For M2, receive from L1 etc. the blur level rayed, all be a point (big depth of focus) by the M2 imaging of system on detector screen S of turning back; S is image planes.Figure 15 is a kind of discrete multiple-point focusing bucking-out system lens-shape figure of the present invention.Figure 16 is a kind of continuous multiple-point focusing bucking-out system lens-shape figure of the present invention.

The above only is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the technology of the present invention principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (10)

1. a camera system is characterized in that, described system comprises:

Etc. fuzzy intermediary image deriving means, be used for that the optical information to object space is carried out empty constant optical system and handle, obtain the fuzzy intermediary image such as unconjugated grade of scenery to be measured;

Image processing apparatus is used for fuzzy intermediary image such as described grade is handled, and obtains the final image of described scenery to be measured.

2. camera system as claimed in claim 1, it is characterized in that, fuzzy intermediary image deriving means such as described grade is that afocal is taken the photograph type device far away, effective picked-up object distance that described afocal is taken the photograph type device far away satisfies the requirement of the scopes beyond greater than focal length several times according to the system design precision, realization is to the fuzzy imaging such as non-conjugated grade of this scope, and its output face position is set in f ± Δ short before or after the accurately image planar range of design depth of field correspondence (Δ〉0) zone; It is lens class focusing system, reflection class focusing system or comprehensive catadioptric focusing system that described afocal is taken the photograph type device far away.

3. camera system as claimed in claim 1, it is characterized in that, fuzzy intermediary image deriving means such as described grade is a multiple-point focusing offset-type device, have a few in the design field depth in the visual field of described multiple-point focusing offset-type device is owing to the compensation of multiple-point focusing to different object distances, the point spread function psf approximately equal in the output face; Described multiple-point focusing offset-type device comprises lens class focusing system, reflection class focusing system or the comprehensive catadioptric focusing system of symmetroid.

4. as each described camera system of claim 1 to 3, it is characterized in that fuzzy intermediary image deriving means such as described grade also comprises transmitance decay mask plate, be used to enlarge the scope and the precision of the fuzzy depth of field such as described grade.

5. camera system as claimed in claim 2, it is characterized in that, described image processing apparatus comprises that the output face of taking the photograph type device far away with afocal is that the big F of input aperture counts optical imaging system and corresponding aberration calibration image disposal system, described big F counts first output face coincidence of taking the photograph type device far away with afocal of optical imaging system, in lens combination, its first eyeglass is a field lens; Described device is refraction class lens combination, reflection type systematic or comprehensive catadioptric system.

6. camera system as claimed in claim 5 is characterized in that, described refraction class lens combination such as is at refractive index curved surface refracting medium lens and/or gradient-index lens.

7. as each described camera system of claim 1 to 3, it is characterized in that, described image processing apparatus is the digital picture capturing system, its imaging surface is positioned at etc. in the output face of fuzzy intermediary image deriving means, according to the psf of priori utilize image processing algorithm etc. fuzzy intermediary image revert to picture rich in detail.

8. an image capture method is characterized in that, said method comprising the steps of:

A. will carry out empty constant optical system to the optical information of object space and handle, and obtain the fuzzy intermediary image such as non-conjugated of scenery to be measured;

B. fuzzy intermediary image such as described grade is handled, obtained the final image of described scenery to be measured.

9. image capture method as claimed in claim 8 is characterized in that, described steps A is specially:

A1. will take the photograph type device far away by afocal at the pointolite in waiting fuzzy field depth, the fuzzy intermediary image such as grade of fuzzy characteristics such as one-tenth in short f ± Δ before or after the accurately image planar range of design depth of field correspondence (Δ〉0) zone; Or

A2. will be at the multiple-point focusing offset-type device of the pointolite in waiting fuzzy field depth by symmetroid, the fuzzy intermediary image of fuzzy characteristics such as in output face, form.

10. image capture method as claimed in claim 9 is characterized in that,

When described steps A adopted steps A 1, described step B was specially: fuzzy intermediary image such as described grade is counted optical imaging system by big F assemble, described big F counts first output face coincidence of taking the photograph type device far away with described afocal of optical imaging system;

When described steps A adopted steps A 1 or A2, described step B was specially: according to the psf of priori utilize image processing algorithm etc. fuzzy intermediary image revert to picture rich in detail, described image processing algorithm comprises that dimension receives liftering restoration methods or nonlinear method.

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