CN215181232U - Directional backlight module and directional backlight three-dimensional display device - Google Patents

Abstract

The utility model discloses a directional backlight unit and directional three-dimensional display device that is shaded, this directional backlight unit includes: a blue laser configured to emit blue light; a beam scanning mechanism configured to form a blue dot matrix light source; the optical film group is configured to modulate the blue light dot matrix light source to form a line light source which emits light uniformly; and a first lens array configured to form a directional backlight; the blue laser, the light beam scanning mechanism, the optical film group and the first lens array are sequentially arranged along the direction of a propagation path of the laser light source. The technical scheme of the utility model can increase the color rendering of being shaded, improve the colour gamut scope of demonstration to can effectively eliminate laser speckle and interfere, increase its homogeneity.

Description

Directional backlight module and directional backlight three-dimensional display device

Technical Field

The utility model relates to a bore hole 3D shows technical field, concretely relates to directional backlight unit and directional stereoscopic display device that is shaded.

Background

The naked-eye 3D display technology, also commonly referred to as "naked-eye multi-view" technology, uses an optical method to allow the left and right eyes to see images with different parallaxes, respectively, without using any tool, and reflects them to the brain, thereby forming a stereoscopic sensation in the brain. In the past, naked-eye 3D display technology is one of the directions actively explored and pursued by the industry. When the naked eye 3D display technology is used for watching, a vivid 3D effect can be created without wearing any auxiliary tool (such as glasses, helmets and the like), the existing mature naked eye 3D display technology has parallax barriers, cylindrical lens arrays and the like, and the technologies have some defects which cannot be overcome, such as low image resolution, easy visual fatigue after long-term watching and the like.

With the development of the related art, the problem of resolution loss has been perfectly solved by the directional backlight naked-eye 3D display technology, which realizes the presentation of a 3D image in a manner of not losing resolution by a technology in which an image source is independent of a light source. For example, a directional backlight naked-eye 3D system in the prior art mainly comprises an optical device such as a directional backlight source, a lens array, and an image display layer. The directional backlight source is a light source which is modulated by a lens, and then the divergence angle of the light beam of the light source is restricted so as to project the light beam to a specified area. Among them, the image display device is mainly a liquid crystal panel having a refresh rate of 120Hz or 240 Hz. When the left eye image is refreshed, the corresponding LED of the left eye is turned on, and when the right eye image is refreshed, the corresponding LED of the right eye is turned on. Because the single-eye refresh rate is larger than 60Hz, the phenomena of screen flash and the like can not occur. However, the existing related technologies still have many defects, such as the problem of being limited by the difficulty in manufacturing the linear backlight, the problem of limited color gamut of the backlight, and the high manufacturing cost, and the like, so that the directional backlight naked-eye 3D display technology is attracting much attention.

Most of backlight sources used in the traditional directional backlight naked eye 3D display technology are LED backlight sources, and because the LED backlight sources have high cost and complex control process and are difficult to form fine line light sources, a staggered backlight structure is required, for example, the document of chinese publication No. CN106896518A, which discloses a staggered backlight naked eye 3D display system. Moreover, the traditional directional backlight naked-eye 3D display technology is limited by the problem of poor color rendering of LEDs, the range of the display color gamut of image pictures is limited, and the viewing experience is seriously influenced.

SUMMERY OF THE UTILITY MODEL

In order to solve the problems in the related art, the embodiment of the present invention provides a directional backlight module and a directional stereoscopic display device.

In a first aspect, an embodiment of the present invention provides a directional backlight module.

Specifically, the directional backlight module comprises:

a blue laser configured to emit blue light;

a beam scanning mechanism configured to form a blue dot matrix light source;

the optical film group is configured to modulate the blue light dot matrix light source to form a line light source which emits light uniformly; and a first lens array configured to form a directional backlight; wherein the content of the first and second substances,

the blue laser, the light beam scanning mechanism, the optical film group and the first lens array are sequentially arranged along the direction of a light propagation path.

In combination with the first aspect, in a first implementation manner of the first aspect, the beam scanning mechanism may be a galvanometer laser scanning system.

Combine the first implementation of first aspect, the utility model discloses in the second implementation of first aspect, wherein, galvanometer formula laser scanning system includes that X axle galvanometer scanning lens, Y axle galvanometer scanning lens and field lens shake, through control X axle galvanometer scanning lens and Y axle galvanometer scanning lens modulation the blue light is in order to form blue light dot matrix light source, blue light dot matrix light source warp project behind the field lens focus the appointed area of first blooming carries out scanning point by point.

With reference to the first aspect, the first implementation manner and the second implementation manner of the first aspect, in a third implementation manner of the first aspect, the optical film group at least includes a first optical film and a second optical film, and the first optical film and the second optical film are sequentially arranged along the light propagation path.

With reference to the third implementation manner of the first aspect, in a fourth implementation manner of the first aspect, the first optical film may be a quantum dot film.

Combine the fourth implementation of the first aspect, the utility model discloses in the fifth implementation of the first aspect, the quantum dot membrane has ruddiness quantum dot and green glow quantum dot, throws quantum dot membrane is last blue light dot matrix light source arouses the quantum dot material and generates white light dot matrix light source.

Combine the fifth implementation of the first aspect, the utility model discloses in the sixth implementation of the first aspect, the second optical film is linear diffusion barrier, white light dot matrix light source warp form the even luminous line light source behind the diffusion adjustment of linear diffusion barrier.

With reference to the sixth implementation manner of the first aspect, in a seventh implementation manner of the first aspect, the linear diffusion film is disposed between the quantum dot film and the first lens array, and is spaced apart from the quantum dot film by a first predetermined distance.

With reference to the first aspect, the first implementation manner, the second implementation manner, the fourth implementation manner to the seventh implementation manner of the first aspect, the present invention provides an eighth implementation manner of the first aspect, wherein the first lens array is a linear fresnel lens array or a cylindrical lens array, and the uniformly luminous line light source passes through the modulation of the first lens array to form a directional backlight source.

Combine the second implementation of the first aspect, the utility model discloses in the ninth implementation of the first aspect, wherein, blue light dot matrix light source's vertical interval should be less than or equal to 8mm, and horizontal interval should be less than or equal to 1.25 mm.

With reference to the sixth implementation manner and the seventh implementation manner of the first aspect, in a tenth implementation manner of the first aspect, the linear diffusion film has a lateral diffusion angle ranging from 1 ° to 1.5 °, and a longitudinal diffusion angle ranging from 40 ° to 80 °.

In a second aspect, embodiments of the present invention provide a directional backlight stereoscopic display device.

Specifically, the display device includes:

the device comprises a directional backlight module, an image display unit positioned in front of the directional backlight module and a driving device for driving the image display unit; the directional backlight module is the first aspect, and any one of the first implementation manner to the tenth implementation manner of the first aspect.

According to the utility model provides a technical scheme, a directional backlight unit includes: a blue laser configured to emit a blue laser light source; a beam scanning mechanism configured to form a blue dot matrix light source; the optical film group is configured to modulate the blue light dot matrix light source to form a line light source which emits light uniformly; and a first lens array configured to form a directional backlight; the blue laser, the light beam scanning mechanism, the optical film group and the first lens array are sequentially arranged along the direction of a propagation path of the laser light source. The utility model provides a directional backlight unit has high color rendering, high homogeneity and good controllability for traditional bore hole 3D backlight. Specifically, a high-power blue laser is modulated to form a blue dot matrix light source in a very short time through a high-speed light beam scanning mechanism, and the blue dot matrix light source is projected on a first optical film of an optical film group to be excited to form a white dot matrix light source, so that the color rendering of the backlight can be increased, and the color gamut range of the display is improved; the laser speckle interference is eliminated and the uniformity is increased through the adjustment of a second optical film of the optical film group; the directional backlight source for naked eye 3D display can be formed through modulation of the first lens array, and display quality can be remarkably improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.

Drawings

Other features, objects and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments thereof, when taken in conjunction with the accompanying drawings. In the drawings:

fig. 1 shows a schematic structural diagram of a directional backlight module according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of an optical film group of a directional backlight module according to an embodiment of the present invention;

fig. 3 shows the light path schematic diagram after the blue light lattice light source projects to the quantum film according to the embodiment of the present invention.

Wherein:

100-a directional backlight module; 101-a laser light source module; 102-a beam scanning mechanism; 103-a first optical film; 103-1-blue light excitation white light lattice light source; 104-a second optical film; 104-1-diffused line light source; 105-a first lens array;

201-X axis galvanometer scanning lens; 202-Y axis galvanometer scanning lens; 203-field lens.

Detailed Description

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them. Also, for the sake of clarity, parts not relevant to the description of the exemplary embodiments are omitted in the drawings.

In the present invention, it is to be understood that terms such as "including" or "having," etc., are intended to indicate the presence of the disclosed features, numbers, steps, actions, components, parts, or combinations thereof, and are not intended to preclude the possibility that one or more other features, numbers, steps, actions, components, parts, or combinations thereof may be present or added.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is conventionally placed when the present invention is used, and are only for convenience of description of the present invention and simplification of description, but do not indicate or imply that the device or element to which the present invention is directed must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

It should be further noted that the embodiments and features of the embodiments of the present invention may be combined with each other without conflict. The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

In the foregoing, most of the backlight sources used in the conventional directional backlight naked-eye 3D display technology are LED backlights, and since the LED backlight sources are high in cost and complex in control process, and it is difficult to form a fine line light source, a staggered backlight structure is required, which increases the control difficulty, and suffers from the problem of poor color rendering of LEDs, the display color gamut range of image frames is limited, and the viewing quality of viewers is seriously affected.

In order to solve the above-mentioned defect, the utility model provides a directional backlight module, include: the system includes a blue laser emitting blue laser light, a beam scanning mechanism configured to form a blue dot matrix light source, a first optical film configured to generate a white dot matrix light source, a second optical film configured to form a line source that uniformly emits light, and a first lens array configured to form a directional backlight. And the modules are arranged in sequence along the direction of the propagation path of the laser light. The technical scheme of the utility model can promote the color gamut performance by a wide margin, let the color more vivid to effectively eliminate and interfere the speckle, reduce and show the interference, thereby show and promote display quality.

Fig. 1 shows a schematic structural diagram of a directional backlight module according to an embodiment of the present invention. As shown in fig. 1, the directional backlight module includes:

a blue laser 101 configured to provide a blue laser light source;

a beam scanning mechanism 102 configured to form a blue dot matrix light source;

the optical film groups 103 and 104 are configured to modulate the blue light dot matrix light source to form a line light source which uniformly emits light; and

a first lens array 105 configured to form a directional backlight; wherein the content of the first and second substances,

the laser light source module 101, the beam scanning mechanism 102, the optical film groups 103 and 104, and the first lens array 105 are sequentially arranged along a propagation path direction of the laser light source.

According to the utility model provides a technical scheme, the utility model discloses can adopt laser as the light source, compare in conventional LED light source, characteristics such as its advantage lies in wide colour gamut of laser, long-life, hi-lite, low energy consumption can show in the display technology and promote the colour gamut performance. Specifically, the present invention adopts a blue laser as a laser light source, the blue laser can emit blue laser light with high power, and preferably, in order to effectively improve the display brightness, the output power of the blue laser should be possibly high, for example, greater than 1W, specifically, 2W, 3W, 5W, 8W, 12W, 24W, 36W, etc., and, in order to avoid damaging the optical thin films in the optical film group, such as the quantum dot film, the output power should be controlled below the threshold value of the optical thin films at the same time.

The high-power blue laser light source emitted by the blue laser 101 is modulated by the light beam scanning mechanism 102 to form a blue light lattice light source, after the blue light lattice light source is projected onto the optical film group, the optical film material in the optical film group is firstly excited to generate a white light lattice light source with wider color gamut range and extremely high brightness, then the white light lattice light source can form a linear light source with better uniformity after the interference speckle removal and crosstalk reduction of the optical film group, and finally the linear light source is modulated by the first lens array 105 to form a naked-eye 3D directional backlight source. The utility model provides a directional backlight unit for traditional bore hole 3D backlight, has higher color rendering and homogeneity and good ability of can regulating and control, can show the colour gamut that improves bore hole 3D and show, improves luminance homogeneity and can effectively reduce and crosstalk.

According to an embodiment of the present invention, the beam scanning mechanism 102 may be a galvanometer laser scanning system. It is known to those skilled in the art that due to technical limitations, the conventional scanning galvanometer technology generally has speeds of 10K, 20K, 30K, 40K, 50K and 60K (wherein the scanning speed of the 10K galvanometer is equivalent to running ten thousand points per second), so that the general scanning galvanometer technology cannot form a continuous light source and is difficult to apply to the display field, while the existing scanning galvanometer technology is widely applied to the laser marking field. The utility model discloses it is first time still to use directional backlight with scanning galvanometer technique.

The scanning speed of the galvanometer laser scanning system 102 of the present invention can reach 100K, i.e., 10 ten thousand points per second, which may cause screen flash if it is lower than this value. For example, for a 120Hz naked eye 3D display device, the number of scanning points per frame is equal to the scanning speed/LCD refresh frequency, i.e. the scanning speed per frame reaches 833 points. The utility model discloses a blue light laser beam that sends through blue laser 101 can form continuous light source in the very short time (1/120s) through the polarization scanning of galvanometer formula laser scanning system 102.

As shown in fig. 1, the galvanometer laser scanning system 102 includes an X-axis galvanometer scanning lens 201, a Y-axis galvanometer scanning lens 202, a field lens 203, and a control host computer (not shown in the figure). Wherein, the rotation angle of each galvanometer scanning lens is within the range of +/-30 degrees. The upper computer is controlled to do rapid polarization motion on an X axis and a Y axis respectively through controlling the X-axis galvanometer scanning lens 201 and the Y-axis galvanometer scanning lens 202, and the blue laser beams form a continuous blue light dot matrix light source with certain longitudinal and transverse intervals after being scanned and modulated by two dimensions of the X axis and the Y axis, for example, in order to ensure the continuity after light source diffusion, the longitudinal interval of the blue light dot matrix light source of the utility model is not more than 8mm, and the transverse interval is not more than 1.25 mm; and then, the blue light lattice light source is modulated and focused by a field lens 203 of the laser scanning system and then is projected into a designated area of the optical film group for point-by-point scanning. The embodiment of the utility model discloses a can obtain continuous even light source through being applied to high power laser light source with mirror vibration formula laser scanning system, solve the problem that conventional scanning mirror vibration technique can not form continuous light source.

According to the embodiment of the present invention, the optical film group at least includes a first optical film 103 and a second optical film 104, and the first optical film 103 and the second optical film 104 are sequentially arranged along the light propagation path.

The first optical film 103 may be a quantum dot film. As shown in fig. 2. Fig. 2 is a schematic structural diagram of an optical film group of a directional backlight module according to an embodiment of the present invention.

The quantum dot film is a brand new nano material with unique optical characteristics, and is a wide-color-gamut special optical film which is prepared by taking quantum dots, barrier resin and an optical-grade water-oxygen barrier film as main raw materials and combining a high-precision coating technology. High-energy blue light can be accurately and efficiently converted into red and green light. In the prior art, a general quantum dot film takes a blue light LED as a light source, and the quantum dot film can excite pure green light and pure red light under the excitation of the blue light, so that the blue light is mixed to form full-spectrum white light. The quantum dot display technology has been comprehensively upgraded in various dimensions such as color gamut coverage, color control accuracy, red, green and blue color purity and the like.

However, the excitation light source of the quantum dot film in the prior art is a blue LED, and since the LED is a spectral light source, the spectrum of the light source is very wide, and the advantages of the quantum dot cannot be well exerted, the spectral color gamut formed by the quantum dot is narrow, and the color is not pure enough, and in addition, the quantum film excited by the blue LED cannot well form a fine line light source, and is difficult to be used as a directional backlight source for naked eye 3D.

The embodiment of the utility model provides a technical scheme adopts blue laser 101 to provide blue light laser light source, and the high power blue light that blue laser 101 sent shakes mirror camera lens 201 and the regulation and control that mirror camera lens 202 was shaken in Y axle scanning through X axle scanning, carries out point-by-point scanning through field lens 203 with the light beam projection in quantum dot membrane 103's specified region. Wherein, the utility model discloses a quantum dot membrane 103 has ruddiness quantum dot and green glow quantum dot, and the blue light that blue laser instrument 101 sent carries out point-by-point scanning via galvanometer formula laser scanning system 102 modulation and projection quantum dot membrane 103, excites the quantum dot material production red light and the green light of quantum dot membrane, forms the pure positive white light dot matrix light source of high quality after this red light, green light and the blue light dot matrix light source mix. The embodiment of the utility model provides a excite the backlight of quantum dot membrane by the blue light, easily form the line source when guaranteeing to obtain high colour gamut characteristic, can solve current blue light LED well and make the spectrum colour gamut that the quantum dot formed narrow, the colour is not pure just to and the quantum dot membrane is aroused by blue light LED, can not form the line source, is difficult to regard as the problem of bore hole 3D with directional backlight.

As shown in fig. 2, the second optical film 104 is disposed behind the quantum dot film 103 along the optical path, and the second optical film 104 of the embodiment of the present disclosure may be a linear diffusion film, wherein the linear diffusion film is a film layer capable of polarizing and mainly functions to refract, reflect and scatter light rays when the light rays pass through media with different refractive indexes.

The white light lattice light source 103-1 formed by the quantum dot film 103 can form a line light source which can uniformly emit light after being diffused and adjusted by the linear diffusion film 104. Through the adjustment of the linear diffusion film 104, laser speckle interference can be eliminated, display interference is reduced, and uniformity is increased.

Fig. 3 shows the light path schematic diagram after the blue light lattice light source projects to the quantum film according to the embodiment of the present invention.

Referring to fig. 2 and 3, the linear diffusion film 104 of the embodiment of the present invention is disposed between the quantum dot film 103 and the first lens array 105, wherein the linear diffusion film 104 is spaced apart from the quantum dot film 103 by a first predetermined distance d1, the first predetermined distance d1 is related to the diffusion angle θ of the linear diffusion film 104 and the distance s between two adjacent laser dots, and the first predetermined distance d1 can be determined by using the following formula (1):

tan(θ/2)＝s/(2*d1) (1)

where the angle θ is the lateral or longitudinal diffusion angle of the linear diffusion film 104 and s is the spacing between adjacent lateral or longitudinal laser spots. It is understood that the θ angle of the present disclosure may be a diffusion angle in a transverse or longitudinal direction of the linear diffusion film, and when the spacing s is a spacing between adjacent transverse laser spots, the θ angle is a transverse diffusion angle; when the spacing s is the spacing between adjacent longitudinal laser points, the angle θ at this time is the longitudinal diffusion angle.

The white light lattice light source 103-1 generated by excitation on the quantum dot film 103 can be transversely and longitudinally diffused by the linear diffusion film 104, wherein the transverse diffusion angle is smaller than the longitudinal diffusion angle. For example, in order to ensure the linearity of the dot matrix light source and simultaneously improve the uniformity of the light source, the linear diffusion film of the present invention can realize the transverse small angle diffusion of the white dot matrix light source, for example, between 1 ° and 1.5 °, and the longitudinal large angle diffusion, for example, between 40 ° and 80 °, so as to form a uniform continuous line light source. The transverse diffusion angle of the present embodiment cannot be too large, which would otherwise result in too high crosstalk, while the longitudinal large angle diffusion can increase the uniformity of the line light source.

According to the embodiment of the present disclosure, as shown in fig. 2, the white-light lattice light source 103-1 generated by blue light excitation has a lateral laser spot spacing s of 5/4 ═ 1.25mm in the x direction (i.e., lateral direction) of the white-light lattice light source 103-1, and the lateral diffusion angle θ of the linear diffusion film 104 can be determined according to the above formula (1):

θ＝2arctan(s/2*d1)

when the transverse diffusion angle θ is 1.5 °, the first predetermined distance d1 is 47.7mm, and at this time, to ensure uniformity, the longitudinal diffusion angle of the linear diffusion film 104 in the y direction (i.e., the longitudinal direction) may be 40 °, so that the white light lattice light source 103-1 may be adjusted by the linear diffusion film 104 to form the continuous line light source 104-1. As shown in fig. 2 and 3.

The utility model discloses a pseudo-random structure on linear diffusion film surface can effectively eliminate the interference speckle that laser produced as the display light source, reduces the demonstration and disturbs, increases the homogeneity to show promotion display quality.

According to the embodiment of the present invention, the first lens array 105 may be a linear fresnel lens array or a cylindrical lens array, and the uniformly luminous line light source forms a directional backlight source after being modulated by the first lens array 105, and the directional backlight source focuses on the viewing area range of the corresponding image display unit, such as the display area of the liquid crystal display screen, through the linear fresnel lens array or the cylindrical lens array.

As shown in fig. 1 and 2, the linear fresnel lens array 105 employed in the embodiments of the present disclosure may include, for example, 8 cells, each of which has a width of 44mm, so that its overall width is 352 × 200mm, and may constitute a 16-inch display cell. In 3D image refresh, each of the 8 cells of the linear fresnel lens array 105 may correspond to 8 sets of linear backlights per frame, and the scanning galvanometer of the galvanometer laser scanning system 102 may scan 833 dots per frame, that is, each set corresponds to 833/8-104.125 dots, where the maximum integer is taken to be 104 dots. Since each lens unit of each frame can correspond to 104 points, when 104 points are projected on the quantum dot film 103 within the range of 5 x 200mm to form a lattice of 4 x 26, the blue light lattice excites the quantum film 103 to emit white light, and a linear light source 104-1 of 5 x 200mm is formed through the diffusion effect of the linear diffusion film 104 and is modulated by the Fresnel lens 105 to form a directional backlight source.

In an embodiment of the present invention, the linear fresnel lens array or the cylindrical lens array is separated from the viewing area of the image display unit by a third predetermined distance, and the third predetermined distance enables no moire fringe effect to be generated.

For example, when the line light source width L1 modulated by the linear diffusion film 104 is 5mm, the second predetermined distance d2 between the quantum dot film 103 and the fresnel lens array 105 is 66mm, and the optimal viewing distance (i.e., the third predetermined distance from the linear fresnel lens array 105 to the vision of the image display unit) S1 is 800mm, which can be calculated according to the triangle-like principle, and the light spot width W at the optimal viewing position is S1L 1/d2 is 60.6mm, which is smaller than the human eye pupil distance 63mm, so that no crosstalk is formed.

To enable a balance between the aberrations and the viewing zone, embodiments of the present invention preferably control the ratio of the focal length (i.e., focal length/aperture) of the linear fresnel lens array 105, for example, between 1.50 and 1.58.

According to the above embodiment of the utility model, the high power blue light laser light source that blue laser sent passes through galvanometer formula laser scanning system's regulation and control, projects blue light dot matrix light source to the quantum dot membrane through the field lens and carries out the point-by-point scanning and form blue light excited white light dot matrix light source, increases its colour rendering to through the adjustment of linear diffusion film, effectively eliminate the speckle and interfere, increase the homogeneity, at last via cylindrical lens array or linear fresnel lens array modulation, form bore hole 3D and show and use directional backlight.

According to another embodiment of the present invention, a directional backlit stereoscopic display device is provided.

The directional backlight stereoscopic display device comprises: a directional backlight module 100, an image display unit located in front of the directional backlight module 100, and a driving device for driving the image display unit. Wherein the content of the first and second substances,

the directional backlight module 100 includes: a laser light source module 101 configured to provide a blue laser light source; a beam scanning mechanism 102 configured to form a blue dot matrix light source; an optical film group including at least a first optical film 103 and a second optical film 104, wherein the first optical film 103 is configured to generate a white light lattice light source 103-1; a second optical film 104 configured to form a line light source 104-1 that uniformly emits light; and a first lens array 105 configured to form a directional backlight; the laser light source module, the light beam scanning mechanism, the first optical film, the second optical film and the first lens array are sequentially arranged along the direction of a propagation path of the laser light source.

According to the technical scheme provided by the embodiment of the utility model, the blue laser 101 can emit a high-power blue laser light source; the light beam scanning mechanism 102 may be a galvanometer laser scanning system, and may modulate a blue laser light source to form a blue dot matrix light source; the first optical film 103 may be a quantum dot film, and a blue dot matrix light source formed by modulation by the galvanometer laser scanning system 102 is projected onto the quantum dot film 103 to perform point-by-point scanning, so that a quantum dot material of the quantum dot film can be excited to form a high-quality white dot matrix light source 103-1; the second optical film 104 can be a linear diffusion film, and the white light lattice light source 103-1 formed by modulation of the quantum dot film 103 can eliminate speckle interference and increase uniformity by modulation of the linear diffusion film 104; the first lens array 105 may be a cylindrical lens array or a linear fresnel lens array, and the homogenized linear light source is modulated by the cylindrical lens array or the linear fresnel lens array to finally form a directional backlight source for naked-eye 3D display, and the directional backlight source is focused to a visual area range of a corresponding image display unit, for example, a display area of a liquid crystal display screen by the cylindrical lens array or the linear fresnel lens array.

The utility model provides a pair of directional backlight unit and directional stereoscopic display device that is shaded, the regulation and control that the high power blue light that utilizes the blue laser to send passes through galvanometer formula laser scanning system, through the field lens with the light beam projection quantum dot membrane carry out the point-by-point scanning formation blue light arouses white light dot matrix light source, increase its colour rendering, through the adjustment of linear diffusion barrier, eliminate the speckle and interfere, increase its homogeneity, at last by cylindrical lens array or linear fresnel lens array modulation, form bore hole 3D and show and use directional backlight. The problems that naked eye 3D display in the prior art is limited by a linear backlight source and is difficult to manufacture, the color gamut range of the backlight source is limited, an LED backlight source is used in an existing naked eye 3D display, fine line light sources are difficult to form, a staggered backlight structure needs to be adopted, the control difficulty is increased and the like are solved, meanwhile, the galvanometer type laser scanning technology is applied to directional backlight, a blue light laser light source is used for exciting a quantum dot film, the problem that a continuous light source cannot be formed in a common scanning galvanometer technology and is difficult to apply to the display field, the quantum dot film is excited by a blue light LED, the line light sources cannot be formed, and the problem that the quantum dot film is difficult to serve as the directional backlight source for naked eye 3D is solved.

According to another embodiment of the present disclosure, there is provided a method for forming a directional backlight, including the steps S101 to S105 of:

in step S101: providing a laser light source module, wherein the laser light source module emits a blue laser light source;

in step S102: providing a light beam scanning mechanism, wherein the blue laser light source is modulated by the light beam scanning mechanism to form a blue dot matrix light source;

in step S103: arranging an optical film group along the propagation path direction of the blue light lattice light source, wherein the optical film group at least comprises a first optical film and a second optical film, and the blue light lattice light source is projected to the first optical film and then is excited to generate a white light lattice light source;

in step S104: the white light lattice light source is adjusted into a line light source which uniformly emits light through the second optical film;

in step S105: and providing a first lens array, and modulating the uniformly luminous line light source through the first lens array to form a directional backlight source.

The conventional directional backlight source for naked eye 3D display is mostly an LED backlight source, the LED light source has high cost and complex control, and a staggered backlight structure is required, so the control difficulty is increased; meanwhile, the LED backlight light source is difficult to form a fine line light source, and the color rendering property is poor, so that the experience of audiences is seriously influenced. According to the technical scheme provided by the embodiment of the disclosure, a laser light source module capable of emitting a blue light laser light source is adopted as a backlight light source, for example, a blue light laser with an output wavelength within a range of 400nm-500nm, preferably, the laser module can be a blue light semiconductor laser, and can emit high-power blue light.

According to the blue laser light source emitted by the blue laser, for example, the high-power blue light is modulated to form the blue dot matrix light source in a very short time by using the high-speed light beam scanning mechanism, wherein the high-speed light beam scanning mechanism is preferably a galvanometer laser scanning system. The inventor researches and finds that the galvanometer type laser scanning technology has wide application in the field of laser marking, however, the application of the galvanometer type laser scanning technology to the directional backlight technology is the first time.

The galvanometer type laser scanning system comprises an X-axis galvanometer scanning lens, a Y-axis galvanometer scanning lens, a field lens and a control upper computer. Wherein, the rotation angle of each galvanometer scanning lens is within the range of +/-30 degrees. And the upper computer is controlled to carry out rapid polarization motion on an X axis and a Y axis respectively by controlling the X-axis galvanometer scanning lens and the Y-axis galvanometer scanning lens, and the blue laser beam is scanned and modulated by two dimensions of the X axis and the Y axis to form a continuous blue dot matrix light source with certain longitudinal and transverse intervals. The scanning speed of the galvanometer laser scanning system can reach 100K, namely 10 ten thousand points per second, and if the scanning speed is lower than the scanning speed, screen flash can be caused. For example, for a 120Hz naked eye 3D display device, the number of scanning points per frame is equal to the scanning speed/LCD refresh frequency, i.e. the scanning speed per frame reaches 833 points. The blue laser beam emitted by the blue laser can be adjusted in shape to generate a uniform continuous light source in a very short time (1/120s) through the polarization scanning of the galvanometer laser scanning system, and the continuous light source can be projected to a specified area of other optical devices in the light path direction to be further scanned point by point after being focused by the field lens. The embodiment of the disclosure can obtain a continuous and uniform blue light lattice light source by modulating the galvanometer type laser scanning system applied to the high-power blue light source, thereby solving the problem that the conventional scanning galvanometer technology cannot form a continuous light source.

According to the embodiment of the disclosure, the uniform continuous blue dot matrix light source modulated and formed by the galvanometer laser scanning system in step S102 is focused by the field lens and then projected to a designated area of a first optical film for point-by-point scanning, wherein the first optical film is a quantum dot film, the quantum dot film has red light quantum dots and green light quantum dots, in step S103, the blue dot matrix light source can excite quantum dot materials of the quantum dot film to generate red light and green light, and the red light, the green light and the blue dot matrix light source are mixed to form a high-quality pure white dot matrix light source. The backlight source of the quantum dot film excited by the blue light is easy to form a line light source while high color gamut characteristics are ensured, and the problems that the spectral color gamut formed by quantum dots is narrow and the color is not pure due to the fact that the existing blue light LED is excited by the blue light LED, the line light source cannot be formed, and the line light source cannot be used as a directional backlight source for naked eye 3D are solved.

In step S104, the white light lattice light source formed by the quantum dot film in step S103 may be subjected to diffusion adjustment by the second optical film to form a line light source emitting light uniformly. The second optical film may be a linear diffusion film, which is a polarizing film layer and mainly functions to refract, reflect and scatter light when passing through media with different refractive indexes. Wherein the linear diffusion film is disposed between the quantum dot film and the first lens array, wherein the linear diffusion film is spaced apart from the quantum dot film by a first predetermined distance d 1. The white light lattice light source generated by excitation on the quantum dot film can be subjected to transverse angle diffusion and longitudinal angle diffusion through the linear diffusion film, wherein the transverse diffusion angle is smaller than the longitudinal diffusion angle. For example, in order to ensure the linearity of the dot matrix light source and simultaneously better improve the uniformity of the light source, the linear diffusion film of the present disclosure can realize the transverse small-angle diffusion, for example, 1 ° to 1.5 °, and the longitudinal large-angle diffusion, for example, 40 ° to 80 °, of the white dot matrix light source.

The pseudo-random structure on the surface of the linear diffusion film can effectively eliminate interference speckles generated by laser as a display light source, reduces display interference, increases uniformity and remarkably improves display quality.

In step S105, the line light source that emits light uniformly and formed by the linear diffusion film in step S104 is modulated by the first lens array, and finally a directional backlight is formed. The first lens array can be a linear Fresnel lens array or a cylindrical lens array, and the uniformly luminous line light source is modulated by the linear Fresnel lens array or the cylindrical lens array to form a directional backlight source.

Taking a linear fresnel lens array as an example, for example, the linear fresnel lens array of the present disclosure may include 8 cells, each of which has a width of 44mm, so that the overall width is 352 × 200mm, and a 16-inch display cell may be constructed. For example, in 3D image refresh, since each lens unit of each frame can correspond to 104 dots, the 104 dots are projected on a quantum dot film within the range of 5 × 200mm to form a 4 × 26 dot matrix, the blue dot matrix excites the quantum dot film to emit white light, and through diffusion of a linear diffusion film, a line light source of 5 × 200mm is formed, and a directional backlight source is formed through modulation of a fresnel lens.

To enable a balance between aberrations and viewing field, embodiments of the present disclosure preferably control the ratio of focal diameters (i.e., focal length/aperture) of the linear fresnel lens array, for example, between 1.50 and 1.58.

According to the embodiment of the disclosure, the high-power blue laser light source emitted by the blue laser is regulated and controlled by the galvanometer type laser scanning system, the blue dot matrix light source is projected to the quantum dot film through the field lens to perform point-by-point scanning to form the blue light excited white dot matrix light source, the color rendering property of the white dot matrix light source is improved, the speckle interference is effectively eliminated through the adjustment of the linear diffusion film, the uniformity is improved, and finally the directional backlight source for naked eye 3D display is formed through the modulation of the linear Fresnel lens array.

The above description is only a preferred embodiment of the invention and is intended to illustrate the technical principles applied. It will be understood by those skilled in the art that the scope of the present invention is not limited to the specific combination of the above-mentioned features, and other embodiments formed by any combination of the above-mentioned features or their equivalents may be covered without departing from the spirit of the invention. For example, the above features and (but not limited to) technical features having similar functions disclosed in the present invention are mutually replaced to form the technical solution.

Claims (12)

1. A directional backlight module, comprising:

a blue laser configured to emit blue light;

a beam scanning mechanism configured to form a blue dot matrix light source;

the optical film group is configured to modulate the blue light dot matrix light source to form a line light source which emits light uniformly; and

a first lens array configured to form a directional backlight; wherein the content of the first and second substances,

the blue laser, the light beam scanning mechanism, the optical film group and the first lens array are sequentially arranged along the direction of a light propagation path.

2. A directional backlight module according to claim 1, wherein: the optical film group at least comprises a first optical film and a second optical film, and the first optical film and the second optical film are sequentially arranged along a light propagation path.

3. A directional backlight module according to claim 2, wherein: the light beam scanning mechanism is a galvanometer type laser scanning system.

4. A directional backlight module according to claim 3, wherein: the galvanometer type laser scanning system comprises an X-axis galvanometer scanning lens, a Y-axis galvanometer scanning lens and a field lens, the X-axis galvanometer scanning lens and the Y-axis galvanometer scanning lens are controlled to modulate blue light to form a blue light dot matrix light source, and the blue light dot matrix light source is focused by the field lens and then projected to a designated area of the first optical film to be scanned point by point.

5. A directional backlight module according to claim 4, wherein: the first optical film is a quantum dot film.

6. A directional backlight module according to claim 5, wherein: the quantum dot film is provided with red light quantum dots and green light quantum dots, and the blue light lattice light source projected on the quantum dot film excites the quantum dot material to generate a white light lattice light source.

7. A directional backlight module according to claim 6, wherein: the second optical film is a linear diffusion film, and the white light lattice light source is subjected to diffusion adjustment of the linear diffusion film to form a uniformly luminous line light source.

8. A directional backlight module according to claim 7, wherein: the linear diffusion film is disposed between the quantum dot film and the first lens array and spaced apart from the quantum dot film by a first predetermined distance.

9. A directional backlight module according to any one of claims 1 to 3 and 5 to 8, wherein: the first lens array is a linear Fresnel lens array or a cylindrical lens array, and the uniformly luminous line light source is modulated by the first lens array to form a directional backlight source.

10. A directional backlight module according to claim 3, wherein: the longitudinal distance of the blue light lattice light source is less than or equal to 8mm, and the transverse distance of the blue light lattice light source is less than or equal to 1.25 mm.

11. A directional backlight module according to claim 7 or 8, characterized in that: the transverse diffusion angle of the linear diffusion film is 1-1.5 degrees, and the longitudinal diffusion angle is more than or equal to 40-80 degrees.

12. A directional backlight stereoscopic display device, comprising the directional backlight module as claimed in any one of claims 1 to 11, an image display unit located in front of the directional backlight module, and a driving device for driving the image display unit.

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