CN105759431A - Three-dimensional light field displaying system - Google Patents

Abstract

The invention discloses a three-dimensional light field displaying system which comprises a display, a lens array, and a holographic function screen. The display is used for displaying a preset disparity sub image array. The lens array is used for projecting the preset disparity sub image array to the holographic function screen. The holographic function screen is used for providing a light field with a full parallax three-dimensional effect, wherein the lens in the lens array has a lens with an eccentric pupil. The lens array satisfies the following condition that the flare angle of the center of the disparity sub image in an ith row and an jth column of the preset disparity sub image array relative to the light through round hole of the lens Lij of the corresponding position in the lens array is U, I is an integer which is not larger than the row number of the disparity sub image array, and j is an integer which is not larger than the column number of the disparity sub image array.

Description

A kind of 3 d light fields display system

Technical field

The present invention relates to Display Technique field, be specifically related to a kind of 3 d light fields display system based on spherical substrate eccentric pupil fresnel lens array.

Background technology

Traditional display mode based on slit grating and Lenticular screen cannot provide the parallax of a continuously smooth due to the restriction of viewpoint, and also can only provide the parallax of continuously smooth within the scope of a less viewing angle based on the display mode of high density viewpoint.

The proposition of many projected light displaying mode solves the problems referred to above, and it is a kind of display mode that can reconstruct target object light field based on pixel, and this display packing can provide the parallax of continuously smooth within the scope of a bigger viewing angle.But, the equipment that this display mode needs is more complicated and takies again bigger space.

Based on liquid crystal display (LiquidCrystalDisplay, the proposition of light displaying mode LCD) solves the problems referred to above, in this display mode, each parallax subgraph of the upper display of LCD and corresponding imaging len thereof have formed a unit being similar to projector, by reducing the clear aperature of imaging len and reducing because the problem of image blur brought of the aberration of imaging len.

The existing light displaying mode Problems existing based on LCD is as follows: owing to the clear aperature (i.e. the aperture of logical light circular hole) of imaging len reduces, as shown in Figure 1, for the parallax subgraph (in 1 the parallax subgraph of the leftmost side) of LCD marginal portion, there is an offset distance d at its corresponding imaging len center, center of this parallax subgraph₁, the clear aperature of imaging len is that D, D meet: S=N × D, N are the line number of parallax subgraph array, and S is the spacing of colleague's adjacent parallax subgraph, D in Fig. 1 in parallax subgraph array₁For the spacing of LCD Yu lens arra, the center of the parallax subgraph of the leftmost side is U relative to the subtended angle of the logical light circular hole of the lens of the leftmost side in lens arra₂, the center of middle parallax subgraph is U relative to the subtended angle of the logical light circular hole of the lens in the middle of lens arra₁, U₁With U₂Meet following formula:

$U_1=\arctan \frac{D}{2D_1},U_2=\frac{1}{2}[\arctan \left(\frac{d_1+\frac{D}{2}}{D_1}\right)-\arctan \left(\frac{d_1-\frac{D}{2}}{D_1}\right)].$

The illumination of image plane center (i.e. hologram functional screen center) meets:

$\begin{array}{c}{E}_1=\frac{\mathrm{k\πL}{\sin }^2{U}_1}{{\mathrm{\β}}^2}\\ E_2=\frac{\mathrm{k\πL}{\sin }^2{U}_2}{{\mathrm{\β}}^2}\end{array},$

Wherein, E₁For the image plane center illumination of middle parallax subgraph, E₂For the image plane center illumination of the parallax subgraph of the leftmost side, k is absorptance, and β is amplification, and L is the brightness of LCD.

Visible, due to U₂< U₁, so E₂Less than E₁, so the illumination in image planes is lowered.

Summary of the invention

The technical problem to be solved is the existing light displaying mode based on LCD owing to the clear aperature of imaging len reduces, parallax subgraph for LCD marginal portion, there is the skew of certain distance at these its corresponding imaging len centers, parallax subgraph center, so the illumination in image planes is lowered by a lot of problems.

For this purpose it is proposed, first aspect, the present invention provides a kind of 3 d light fields display system, and described system includes: display, lens arra, hologram functional screen；

Described display is for showing default parallax subgraph array；

Described lens arra is for by described default parallax subgraph array projection to described hologram functional screen；

Described hologram functional screen is for providing the light field with full parallax stereoeffect；

Wherein, the lens in described lens arra are the lens with eccentric pupil, and described lens arra meets following condition:

Described default parallax subgraph array is arranged in the center lens L relative to described lens arra relevant position of the parallax subgraph that the i-th row jth arranges_ijThe subtended angle of logical light circular hole be U, i be the positive integer being not more than parallax subgraph array line number, j is the positive integer being not more than parallax subgraph array columns.

Optionally, described display is liquid crystal display LCD, and the lens in described lens arra are Fresnel Lenses.

Optionally, the lens number in described lens arra is determined by the parallax subgraph number in described default parallax subgraph array.

Optionally, the parallax subgraph number in described default parallax subgraph array is N × N, and described N is positive integer, and the lens number in described lens arra is also N × N.

Optionally, the lens in described lens arra are lighttight square structure, and the center of described square structure has a logical light circular hole.

Optionally, described subtended angle meets:

$U=\arctan \frac{D}{2D_1};$

Wherein, D is the aperture of described logical light circular hole, D₁Spacing for described display Yu described lens arra.

Optionally, described in have eccentric pupil lens logical light circular hole by default lens intercept border circular areas obtain, the center of described border circular areas meet:

$x_1=\frac{D_1}{D_1+D_2}X;$

$y_1=\frac{D_1}{D_1+D_2}Y;$

Wherein, x₁For the horizontal range at center of center and the described default lens of border circular areas, y₁For the vertical distance at center of center and the described default lens of border circular areas, D₂Distance for described lens arra Yu described hologram functional screen, X is the center horizontal range with hologram functional screen center of parallax subgraph, Y is the vertical distance at center and the hologram functional screen center of parallax subgraph, and described parallax subgraph is parallax subgraph corresponding with the described lens position with eccentric pupil in default parallax subgraph array.

Optionally, the lens in described lens arra are produced on curvature is C_sSpherical substrate on, and the phase function of lensMeet:

Wherein, G is asphericity coefficient,φ is power of lens, and λ is the wavelength of light wave；Described C_sDetermined by following manner with the value of G:

According to default aberration balancing rule, regulate C_sWith G so that disc of confusion radius is minimum, wherein said disc of confusion radius is determined by the decentration aberration of the described lens with eccentric pupil.

Compared to prior art, the 3 d light fields display system of the present invention is satisfied by being made as by lens arra: in parallax subgraph array, the center of parallax subgraph is U relative to the subtended angle of the logical light circular hole of the lens of relevant position in lens arra, and lens are made as the lens with eccentric pupil and solve prior art Problems existing, it is achieved that the good 3 d light fields of effect shows.

Accompanying drawing explanation

In order to be illustrated more clearly that the embodiment of the present invention or technical scheme of the prior art, the accompanying drawing used required in embodiment or description of the prior art will be briefly described below, apparently, accompanying drawing in the following describes is some embodiments of the present invention, for those of ordinary skill in the art, under the premise not paying creative work, it is also possible to obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 illustrates the light field display system architectures figure based on liquid crystal display LCD；

Fig. 2 illustrates a kind of 3 d light fields display system of the present invention；

Fig. 3 illustrates a kind of 3 d light fields display system of the present invention；

Fig. 4 illustrates that the present invention has the acquisition schematic diagram of the logical light circular hole of the lens of eccentric pupil.

Detailed description of the invention

For making the purpose of the embodiment of the present invention, technical scheme and advantage clearly, below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is explicitly described, it is clear that, described embodiment is a part of embodiment of the present invention, rather than whole embodiments.Based on the embodiment in the present invention, the every other embodiment that those of ordinary skill in the art obtain under not making creative work premise, broadly fall into the scope of protection of the invention.

As in figure 2 it is shown, the open a kind of 3 d light fields display system of the present embodiment, described system includes: display, lens arra, hologram functional screen, and display can be selected for liquid crystal display LCD, and the lens in lens arra can be selected for Fresnel Lenses.

Display is for showing default parallax subgraph array；The number of the parallax subgraph in parallax subgraph array is predetermined value, the image of different parallax subgraph display object different directions；Lens number in lens arra is determined by the parallax subgraph number in the parallax subgraph array preset, as it is shown on figure 3, the parallax subgraph number in parallax subgraph array is 81, namely parallax subgraph array is that 9 row 9 arrange, and the lens number in lens arra is also 81.

Lens arra is for by default parallax subgraph array projection to hologram functional screen；

Hologram functional screen is for providing the light field with full parallax stereoeffect；

Wherein, the lens in lens arra are the lens with eccentric pupil, and lens arra meets following condition: be arranged in the center lens L relative to described lens arra relevant position of the parallax subgraph that the i-th row jth arranges in default parallax subgraph array_ijThe subtended angle of logical light circular hole be U, i be the positive integer being not more than parallax subgraph array line number, j is the positive integer being not more than parallax subgraph array columns.Subtended angle U meets:

$U=\arctan \frac{D}{2D_1};$

Wherein, D is the aperture of described logical light circular hole, D₁Spacing for described display Yu described lens arra.

Visible, the present embodiment, the center of the parallax subgraph of the leftmost side is relative to the subtended angle U of the logical light circular hole of the lens of the leftmost side in lens arra₂=U, the center of middle parallax subgraph is U relative to the subtended angle of the logical light circular hole of the lens in the middle of lens arra₁=U, it follows that, the lens arra with eccentric pupil ensure that edge parallax subgraph (i.e. the parallax subgraph of the leftmost side) too much will not cause that its illuminance of image plane is too low because of deviation lens centre, meanwhile, the lens arra with eccentric pupil also ensure that the final uniformity rebuilding subject image illumination.

In a particular application, as shown in Figure 4, the logical light circular hole of the lens with eccentric pupil obtains by intercepting border circular areas on default lens, and the center of border circular areas meets:

$x_1=\frac{D_1}{D_1+D_2}X;$

$y_1=\frac{D_1}{D_1+D_2}Y;$

Wherein, x₁For the horizontal range at center of center and the described default lens of border circular areas, y₁For the vertical distance at center of center and the described default lens of border circular areas, D₂Distance for lens arra Yu hologram functional screen, X is the center horizontal range with hologram functional screen center of parallax subgraph, Y is the vertical distance at center and the hologram functional screen center of parallax subgraph, and described parallax subgraph is parallax subgraph corresponding with the lens position with eccentric pupil in default parallax subgraph array.

Lens owing to having eccentric pupil can introduce decentration aberration, and in order to reduce the impact of decentration aberration, in the present embodiment, it is C that the lens in lens arra are produced on curvature_sSpherical substrate on, and the phase function of lensMeet:

Wherein, G is asphericity coefficient,φ is power of lens, and λ is the wavelength of light wave；Described C_sDetermined by following manner with the value of G:

According to default aberration balancing rule, regulate C_sWith G so that disc of confusion radius is minimum, wherein, disc of confusion radius is determined by the decentration aberration of the lens with eccentric pupil.

In the present embodiment, the decentration aberration described in the lens of eccentric pupil has four kinds:

$S_1^{*}=S_1$

$S_2^{*}=S_2-4x_1{S}_1$

$S_3^{*}=S_3-2x_1{S}_2+x_1^2{S}_2$

$S_4^{*}=S_4$

$S_1=\frac{h^4{\mathrm{\&phi;}}^3}{4}[{\left(\frac{n}{n-1}\right)}^2+\frac{n+2}{n}{B}^2+\frac{4(n+1)}{n}B+\frac{3n+2}{n}{T}^2]-8\mathrm{\&lambda;}{h}^{4}G$

$S_2=-\frac{h^2{\mathrm{\&phi;}}^{2}J}{2}[\frac{(n+1)}{n}B+\frac{2n+1}{n}T]$

S₃=J²φ

$S_4=\frac{J^2\mathrm{\&phi;}}{n}$

$T=\frac{u+u^{\&prime;}}{u-u^{\&prime;}},A=\frac{\mathrm{\&phi;}}{2\mathrm{\&lambda;}},B=\frac{2C_S}{\mathrm{\&phi;}}$

Wherein,U, u' are the first paraxial rays angle,H is the height of the first paraxial rays and lens intersection point, and n is the refractive index of lens, and J is Lagrange constant.

The technical term that present document relates to is as follows:

Illumination: namely usually said lux degree (lux), represents the luminous flux being subject on shot subject surface unit area.

Aberration: in actual optical system, inconsistent by the result of the result of far-off axle light rays trace gained and paraxial rays trace gained, the deviation of these ideal states with first-order theory (first-order theory or paraxial rays), it is called aberration.

Eccentric pupil: the part pupil face at deviation entrance pupil center.

Decentration aberration: the aberration introduced by eccentric pupil.

Clear aperature: refer to the effective aperture of lens.

Spherical substrate: referring to the spherical substrate with certain curvature, the substrate of tradition Fresnel Lenses is plane.

Parallax: refer to the difference of the subject image obtained from different directions.

Parallax subgraph: refer to the image of the object that different directions obtains.

Hologram functional screen: the optical panel with a diffusion function made by holographic method.

Angle of scattering: the angle of scattering of hologram functional screen point diffusion.

Viewpoint: from the image that one direction of actual object is acquired.

Resolution: refer to the quantity of the pixel comprised in an inch.

Although being described in conjunction with the accompanying embodiments of the present invention, but those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such amendment and modification each fall within the scope being defined by the appended claims.

Claims (8)

1. a 3 d light fields display system, it is characterised in that described system includes:

Display, lens arra, hologram functional screen；

Described display is for showing default parallax subgraph array；

Described lens arra is for by described default parallax subgraph array projection to described hologram functional screen；

Described hologram functional screen is for providing the light field with full parallax stereoeffect；

Wherein, the lens in described lens arra are the lens with eccentric pupil, and described lens arra meets following condition:

Described default parallax subgraph array is arranged in the center lens L relative to described lens arra relevant position of the parallax subgraph that the i-th row jth arranges_ijThe subtended angle of logical light circular hole be U, i be the positive integer being not more than parallax subgraph array line number, j is the positive integer being not more than parallax subgraph array columns.

2. display system according to claim 1, it is characterised in that described display is liquid crystal display LCD, the lens in described lens arra are Fresnel Lenses.

3. display system according to claim 1, it is characterised in that the lens number in described lens arra is determined by the parallax subgraph number in described default parallax subgraph array.

4. display system according to claim 3, it is characterised in that the parallax subgraph number in described default parallax subgraph array is N × N, and described N is positive integer, and the lens number in described lens arra is also N × N.

5. display system according to claim 3, it is characterised in that the lens in described lens arra are lighttight square structure, the center of described square structure has a logical light circular hole.

6. display system according to claim 5, described subtended angle meets:

$U=\arctan \frac{D}{2D_1};$

Wherein, D is the aperture of described logical light circular hole, D₁Spacing for described display Yu described lens arra.

7. display system according to claim 6, it is characterised in that described in have eccentric pupil lens logical light circular hole by default lens intercept border circular areas obtain, the center of described border circular areas meet:

$x_1=\frac{D_1}{D_1+D_2}X;$

$y_1=\frac{D_1}{D_1+D_2}Y;$

Wherein, x₁For the horizontal range at center of center and the described default lens of border circular areas, y₁For the vertical distance at center of center and the described default lens of border circular areas, D₂Distance for described lens arra Yu described hologram functional screen, X is the center horizontal range with hologram functional screen center of parallax subgraph, Y is the vertical distance at center and the hologram functional screen center of parallax subgraph, and described parallax subgraph is parallax subgraph corresponding with the described lens position with eccentric pupil in default parallax subgraph array.

8. display system according to claim 7, it is characterised in that it is C that the lens in described lens arra are produced on curvature_sSpherical substrate on, and the phase function of lensMeet:

Wherein, G is asphericity coefficient,φ is power of lens, and λ is the wavelength of light wave；Described C_sDetermined by following manner with the value of G:

According to default aberration balancing rule, regulate C_sWith G so that disc of confusion radius is minimum, wherein said disc of confusion radius is determined by the decentration aberration of the described lens with eccentric pupil.