CN100561315C

CN100561315C - A kind of optical module of LCD and the pressure beam slice that is used for it

Info

Publication number: CN100561315C
Application number: CNB200810061076XA
Authority: CN
Inventors: 李同
Original assignee: SIDALI PHOTOELECTRIC SCIENCE AND TECHNOLOGY Co Ltd NINGBO
Current assignee: SIDALI PHOTOELECTRIC SCIENCE AND TECHNOLOGY Co Ltd NINGBO
Priority date: 2008-04-29
Filing date: 2008-04-29
Publication date: 2009-11-18
Anticipated expiration: 2028-04-29
Also published as: CN101276097A

Abstract

The invention discloses a kind of pressure beam slice and optical module that is used for LCD optic module, pressure beam slice is by along comprising that with the overlapping setting of incident light vertical direction a plurality of the plane of incidence that is parallel to each other and the pressure beam unit of exit facet form, go into, be provided with between the exit facet at least one group first reflector element and with it quantity equate or equal second reflector element that its quantity subtracts 1 the symmetry of minute surface with it, first reflector element and second reflector element are spaced along the incident light direction, first reflector element comprises with the plane of incidence and is first reflecting surface of 45 and the second parallel with it reflecting surface, second reflector element comprises three reflecting surface and with it parallel four reflecting surface vertical with second reflecting surface, be provided with big convex lens before the plane of incidence, be provided with lenslet behind the exit facet, the optical axis of big convex lens and lenslet overlaps and focus overlaps to form telescopic system, advantage is to utilize reflecting surface to change direction of beam propagation, makes the thickness of optical module obtain reducing significantly.

Description

A kind of optical module of LCD and the pressure beam slice that is used for it

Technical field

The present invention relates to a kind of optical module of LCD, the pressure beam slice that especially relates to a kind of optical module of LCD and be used for it.

Background technology

Because the liquid crystal itself in LCD (LCDs) panel is not luminous, thereby, reach the display imaging effect, need to give the LCD panel that light source is provided, as utilize backlight (transmission-type) or utilize physical environment light (reflective) to illuminate screen.Yet the luminous energy of backlight can not be utilized effectively in colour liquid crystal display device, makes the brightness of display screen of LCD and contrast can't reach good effect.

Along with the continuous expansion in liquid crystal display applications field, the particularly application of large scale liquid crystal display, also more and more higher to the requirement of the brightness of LCDs and contrast.

In order to compensate the low backlight efficiency of light energy utilization of LCD, improve the brightness and the contrast of LCDs, Chinese invention disclosed patent on November 15th, 2006 " optical module and the LCD that are used for LCD " (CN1862337) discloses a kind of optical module and LCD that is used for LCD, this optical module and the LCD that is used for LCD, it comprises the color separation film before placing the preceding pressure beam slice of liquid crystal screen back light source and placing pressure beam slice, pressure beam slice is divided into one group tiny light beam row with a branch of extensible beam, color separation film is divided into white light red, green, primary colors, and be refracted to different positions according to color sequences, owing to introduced color separation film, all luminous energy all is used effectively in the backlight visible light spectrum, its utilization factor improves more than three times, if introduced beam splitting chip again, the luminous energy of all polarization directions of backlight all is used effectively, its utilization factor is enhanced about more than once, this two template of connecting, then can make the overall efficiency of light energy utilization of backlight improve more than six times, the brightness and the contrast of LCDs are significantly improved, energy consumption significantly reduces, and realizes high brightness truly, the LCD of low energy consumption.But this pressure beam slice that is used for the optical module of LCD, shown in 1 among Fig. 1, adopt different major diameter convex lens array of two radius surfaces and minor diameter convex lens array, it has increased the thickness of LCD when having solved brightness and contrast's problem, incompatible with development, widespread use and the people's of LCD demand.

Summary of the invention

Technical matters to be solved by this invention provides a kind of when can effectively guarantee the high backlight efficiency of light energy utilization of LCD and LCDs high brightness and high-contrast, reduces the optical module of LCD of thickness of LCD and the pressure beam slice that is used for LCD optic module greatly.

The present invention solves the problems of the technologies described above the technical scheme that is adopted: a kind of optical module of LCD, comprise pressure beam slice and color separation film, pressure beam slice is made up of with a plurality of pressure beams unit of the overlapping setting of incident light vertical direction the edge, described pressure beam unit comprises the plane of incidence and the exit facet that is parallel to each other, being provided with at least one group first reflector element and quantity between the described plane of incidence and the described exit facet equals the described first reflector element quantity or equals the described first reflector element quantity to subtract 1 and the second reflector element described first reflector element minute surface symmetry, described first reflector element and described second reflector element are spaced along the incident light direction, described first reflector element comprises with the plane of incidence and is first reflecting surface of 45 and second reflecting surface parallel with described first reflecting surface, described second reflector element comprises three reflecting surface and with described three reflecting surface parallel four reflecting surface vertical with described second reflecting surface, be provided with big convex lens before the described plane of incidence, be provided with lenslet behind the described exit facet, the optical axis of described big convex lens and described lenslet overlaps, and focus overlaps to form telescopic system.

Described color separation film comprises the interference filter group, and described interference filter group is made up of three kinds of interference filter repeated arrangement of red, green, blue, and described interference filter is along arranging with the perpendicular direction of incident beam.

Be provided with beam splitting chip between described pressure beam slice and the described color separation film, described beam splitting chip comprises two substrates and is arranged on space orientation liquid crystal molecule between described substrate, described liquid crystal molecule along become with incident beam greater than 0 °, arrange less than 90 ° angle directions.

A kind of pressure beam slice that is used for LCD optic module, it is made up of with a plurality of pressure beams unit of the overlapping setting of incident light vertical direction the edge, described pressure beam unit comprises the plane of incidence and the exit facet that is parallel to each other, being provided with at least one group first reflector element and quantity between the described plane of incidence and the described exit facet equals the described first reflector element quantity or equals the described first reflector element quantity to subtract 1 and the second reflector element described first reflector element minute surface symmetry, described first reflector element and described second reflector element are spaced along the incident light direction, described first reflector element comprises with the plane of incidence and is first reflecting surface of 45 and second reflecting surface parallel with described first reflecting surface, described second reflector element comprises three reflecting surface and with described three reflecting surface parallel four reflecting surface vertical with described second reflecting surface, be provided with big convex lens before the described plane of incidence, be provided with lenslet behind the described exit facet, the optical axis of described big convex lens and described lenslet overlaps, and focus overlaps to form telescopic system.

Described big convex lens are arranged on the described plane of incidence, and described lenslet is arranged on the described exit facet.

Described lenslet is little convex lens.

Described lenslet is little concavees lens.

Compared with prior art, the invention has the advantages that and guaranteeing to constitute under the prerequisite of telescopic system, by changing the composition structure of pressure beam slice, first reflector element that utilization is provided with and the reflecting surface of second reflector element change the direction of propagation from the light of the extensible beam of backlight of LCD, for same propagation distance, the thickness of pressure beam slice has reduced half, when improving LCD brightness and contrast, the thickness of LCD is reduced significantly.

Description of drawings

Fig. 1 is the simplified structure sectional view of prior art optical module, and wherein 1 is pressure beam slice;

Fig. 2 a is a kind of structural section figure of pressure beam slice of the present invention;

Fig. 2 b is another structural section figure of pressure beam slice of the present invention;

Fig. 3 a is the pressure beam unit of the pressure beam slice shown in the pie graph 2a and the optics fundamental diagram of telescopic system thereof;

Fig. 3 b is the pressure beam unit of the pressure beam slice shown in the pie graph 2b and the optics fundamental diagram of telescopic system thereof;

Fig. 4 a is for being provided with the pressure beam slice structural section figure of one first reflector element again between the plane of incidence of the pressure beam slice shown in Fig. 2 a and the exit facet;

Fig. 4 b is the pressure beam slice structural section figure that is provided with two first reflector elements and two second reflector elements between the plane of incidence and the exit facet;

Fig. 5 is the optical module structural drawing of the LCD of the pressure beam slice formation shown in use Fig. 2 a;

Fig. 6 is the optical module structural drawing of the LCD of the pressure beam slice formation shown in use Fig. 2 b;

Fig. 7 is the optics fundamental diagram of color separation film;

Fig. 8 is the optical module structural drawing of the LCD of the pressure beam slice formation shown in use Fig. 4 a;

Fig. 9 is the optical module structural drawing of the LCD of the pressure beam slice formation shown in use Fig. 4 b.

Embodiment

Embodiment describes in further detail the present invention below in conjunction with accompanying drawing.

It is a kind of detailed sectional view of structure of the pressure beam slice 1 of material that Fig. 2 a has provided with optical glass or optical plastic, it is made up of with a plurality of pressure beam unit 2 shown in Fig. 3 a of the overlapping setting of incident light vertical direction the edge, pressure beam unit 2 comprises the plane of incidence 3 and the exit facet 4 that is parallel to each other, be provided with second reflector element 6 of one group of first reflector element 5 and a group and first reflector element, 5 minute surface symmetries between the plane of incidence 3 and the exit facet 4, first reflector element 5 and second reflector element 6 are arranged along the incident light direction, first reflector element 5 comprises first reflecting surface 51 that is 45 with the plane of incidence 3 and second reflecting surface 52 parallel with first reflecting surface 51, second reflector element 6 comprises and vertical the 3rd reflecting surface 61 of second reflecting surface 52 and four reflecting surface 62 parallel with the 3rd reflecting surface 61, the plane of incidence 3 is provided with big convex lens, exit facet 4 is provided with little convex lens, big convex lens and little convex lens optical axis overlap, and focus overlaps to form telescopic system.

Fig. 2 b has provided the pressure beam slice 1 of another kind of structure, pressure beam slice 1 shown in its structure and Fig. 2 a basic identical, the pressure beam slice 1 that difference is this structure is by along forming with a plurality of pressure beam unit 2 shown in Fig. 3 b of the overlapping setting of incident light vertical direction, the exit facet 4 of pressure beam unit 2 is provided with little concavees lens, big convex lens on the plane of incidence 3 and little concavees lens optical axis overlap, and focus overlaps to form telescopic system, this structure is overlapped in outside optical glass or the optical plastic because of the focus of big convex lens and little concavees lens, avoided owing to all converge at the focus place after the parallel beam incident, cause focus place temperature too high and damage optical glass or optical plastic, prolonged the serviceable life of pressure beam slice and LCD, in addition, this structure has further reduced the thickness of pressure beam slice 1.

The main effect of pressure beam slice 1 is after width is this pressure beam slice 1 of light beam process of B1, to be compressed to the penlight that width is B2, and the ratio of compression of pressure beam slice 1 is the radius ratio of big convex lens and little convex lens or little concavees lens.Shown in Fig. 3 a, coming from the extensible beam that the backlight width is B1 (by the photocentre O1 of big convex lens) incides on the big convex lens of the plane of incidence 3, this incident extensible beam does not reflect in the plane of incidence 3, be directly incident on first reflecting surface 51 of first reflector element 5, be reflected according to reflection of light law light, light beam after the reflection is in succession again by second reflecting surface 52, the 3rd reflecting surface 61 of

second reflector element

6 and 62 reflections of the 4th reflecting surface, light beam after repeatedly reflecting incides on the little convex lens of exit facet 4, be compressed into the tiny light beam that width is B2 by little convex lens, the ratio of compression that also is pressure beam slice 1 is B1: B2.When the photocentre O1 of the obstructed excessive convex lens of extensible beam of incident, light beam reflects through big convex lens, repeatedly reflects by plane mirror, at last from little convex lens outgoing again.It is pointed out that no matter how light beam is reflected, and light beam must be by the focus of big convex lens and little convex lens.The width B 2 of tiny light beam should equal the pixel wide of LCDs.Disregarding under the logical light rate factor situation, because of need are compressed into a pixel with two (white and black displays screen) pixels or six (colorful display screen) pixels, so the ratio of compression of pressure beam slice 1 is 2: 1 (white and black displays screen) or 6: 1 (colorful display screen).Can improve the logical light rate of pixel by the ratio of compression of adjusting pressure beam slice 1, if count the logical light rate of pixel, then the ratio of compression of pressure beam slice 1 is greater than 2: 1 (white and black displays screen) or 6: 1 (colorful display screen).

The optics principle of work of the pressure beam unit 2 shown in Fig. 3 b and the optics principle of work of the pressure beam unit 2 shown in Fig. 3 a are basic identical.

Pressure beam slice 1 shown in Fig. 2 a also can adopt the structure shown in Fig. 4 a, along the incident light direction two first reflector elements 5 and one second reflector element 6, the first reflector element 5 and second reflector element 6 being set between the plane of incidence 3 and exit facet 4 is spaced along the incident light direction.Its principle of work is the same with the pressure beam slice 1 shown in Fig. 2 a, and different is, in this structure the extensible beam of incident in pressure beam slice 1 through beam reflection process more frequently.Fig. 4 b has provided the detailed sectional view of the pressure beam slice 1 with two first reflector elements 5 and two second reflector elements 6, and first reflector element 5 and second reflector element 6 are spaced along the incident light direction.And the like, some first reflector elements 5 and second reflector element 6 can be set between the plane of incidence 3 and exit facet 4, but first reflector element 5 and second reflector element 6 are spaced along the incident light direction all the time in these structures, and the quantity that the quantity of second reflector element 6 equals the quantity of first reflector element 5 or equals first reflector element 5 subtracts 1, need equally in addition to guarantee that pressure beam slice 1 forms telescopic system, promptly the little concave lens focus of the big convex lens of the plane of incidence 3 and exit facet 4 is overlapping.In like manner, can between the plane of incidence 3 of the pressure beam slice shown in Fig. 2 b 1 and exit facet 4, some first reflector elements 5 and second reflector element 6 be set.Consider the thickness of pressure beam slice 1, the first many reflector element 5 and second reflector element 6 can be set, because the focal length of big convex lens and lenslet is by the radius-of-curvature decision of light refractive index and the convex surface or the concave surface of lens material, orientation independent with beam propagation, so utilize reflecting surface to change the direction of propagation of light, the light beam number of times that is reflected is many more, and focus is just near more to the air line distance of optical center of lens, has reached the purpose that reduces pressure beam slice 1 thickness.

All optical glass of pressure beam slice 1 or optical plastic surface all are coated with anti-reflection film to optimize transmittance.

Before big convex lens in above-mentioned all pressure beam slices 1 can be arranged at the plane of incidence 3, after lenslet can be arranged at exit facet 4.

Fig. 5 has provided the optical module of pressure beam slice 1 formation of using shown in Fig. 2 a, mainly comprises following three parts: (1) is compressed into one group tiny light beam row with a branch of extensible beam by pressure beam slice 1; (2) white nonpolarized light is divided into the beam splitting chip 7 of two groups of mutually orthogonal linearly polarized photons; (3) white linearly polarized photon is divided into three primary colors, and is refracted to the color separation film 8 of relevant position according to color sequences.

Beam splitting chip 7 is arranged between pressure beam slice 1 and the color separation film 8, beam splitting chip 7 comprises that two is the

substrate

71 and 72 and the sterically defined liquid crystal molecule (SF-PDLC) 73 of the high birefringence rate of 71,72 settings of two substrates of material with optical glass or plastics, liquid crystal molecule 73 along become with incident beam greater than 0 °, arrange less than 90 ° angle directions.Unpolarized tiny light beam is listed in and is separated into two groups of mutually orthogonal linearly polarized photon o light (ordinary light) and e light (extraordinary ray) in this beam splitting chip 7, liquid crystal molecule 73 in the beam splitting chip 7 is arranged and is positioned along the direction that can produce o light and e light maximum separation angle, wherein, angle of departure size is by the crystal orientation of crystal and the birefraction decision of material.Optical glass or plastics outside surfaces all in the beam splitting chip 7 all are coated with anti-reflection film to optimize transmittance.

Color separation film 8 comprises with optical glass or optical plastic being the substrate 84 and the interference filter group of material, the interference filter group is made up of one group of red interference filter 81, green interference filter 82 and blue interference filter 83 repeated arrangement, and interference filter is along arranging with the perpendicular direction of incident beam.The interference filter group is vertical with the white polarized light of outgoing after beam splitting chip 7 beam splitting, and white polarized light is 45 ° in the unilateral incident angle of interference filter.The principle of work of color separation film 8 is the frequency spectrum that needs of initial interference filter transmission, reflects unwanted frequency spectrum, and second, third interference filter then reflects the unwanted frequency spectrum of frequency spectrum, transmission that needs.As shown in Figure 7, if initial interference filter is Red lightscreening plate 81, transmits red frequency spectrum then, reflection green and blue spectrum are in the LCDs pixel simultaneously; Green interference filter 82 reflection green frequency spectrums, while transmission blueness and red spectrum, promptly the green that is reflected by first interference filter is reflected in the LCDs pixel in a little green interference filters 82, and blue spectrum then this interference filter of transmission moves on; When remaining frequency spectrum arrived blue interference filter 83, blue spectrum was reflexed in the LCDs pixel by blue interference filter 83.Through above-mentioned interference filter transmission or reflection, the red, green and blue three primary colors are separated fully and are located, and according to the principle of work of color separation film 8, the tandem compound of three kinds of any two kinds of interference filters of interference filter can be realized trichromatic separation and location equally.Be pointed out that, because of the initial interference filter transmission spectrum of interference filter group in the color separation film 8, other interference filter reflecting spectrum are so pressure beam slice 1 need accurately align with color separation film 8, need be overlapping from the light beam of pressure beam slice 1 with initial interference filter, otherwise can cause the impure of colourity.Substrate 84 outside surfaces of color separation film 8 are coated with anti-reflection film to optimize transmittance.

Fig. 6 has provided the optical module of pressure beam slice 1 formation of using shown in Fig. 2 b; its principle of work is identical with the principle of work of optical module shown in Figure 5; but it is thinner than optical module shown in Figure 5, and has protected optical glass or optical plastic effectively, has prolonged the life-span of optical module.

Fig. 8, Fig. 9 have provided the optical module of pressure beam slice 1 formation of using shown in Fig. 4 a, Fig. 4 b respectively.

Claims

1, a kind of optical module of LCD, comprise pressure beam slice and color separation film, it is characterized in that described pressure beam slice is by along forming with a plurality of pressure beams unit of the overlapping setting of incident light vertical direction, described pressure beam unit comprises the plane of incidence and the exit facet that is parallel to each other, being provided with at least one group first reflector element and quantity between the described plane of incidence and the described exit facet equals the described first reflector element quantity or equals the described first reflector element quantity to subtract 1 and the second reflector element described first reflector element minute surface symmetry, described first reflector element and described second reflector element are spaced along the incident light direction, described first reflector element comprises with the plane of incidence and is first reflecting surface of 45 and second reflecting surface parallel with described first reflecting surface, described second reflector element comprises three reflecting surface and with described three reflecting surface parallel four reflecting surface vertical with described second reflecting surface, be provided with big convex lens before the described plane of incidence, be provided with lenslet behind the described exit facet, the optical axis of described big convex lens and described lenslet overlaps, and focus overlaps to form telescopic system.

2, optical module as claimed in claim 1, it is characterized in that described color separation film comprises the interference filter group, described interference filter group is made up of three kinds of interference filter repeated arrangement of red, green, blue, and described interference filter is along arranging with the perpendicular direction of incident beam.

3, optical module as claimed in claim 1, it is characterized in that being provided with beam splitting chip between described pressure beam slice and the described color separation film, described beam splitting chip comprises two substrates and is arranged on space orientation liquid crystal molecule between described substrate, described liquid crystal molecule along become with incident beam greater than 0 °, arrange less than 90 ° angle directions.

4, a kind of pressure beam slice that is used for LCD optic module, it is characterized in that it is by along forming with a plurality of pressure beams unit of the overlapping setting of incident light vertical direction, described pressure beam unit comprises the plane of incidence and the exit facet that is parallel to each other, being provided with at least one group first reflector element and quantity between the described plane of incidence and the described exit facet equals the described first reflector element quantity or equals the described first reflector element quantity to subtract 1 and the second reflector element described first reflector element minute surface symmetry, described first reflector element and described second reflector element are spaced along the incident light direction, described first reflector element comprises with the plane of incidence and is first reflecting surface of 45 and second reflecting surface parallel with described first reflecting surface, described second reflector element comprises three reflecting surface and with described three reflecting surface parallel four reflecting surface vertical with described second reflecting surface, be provided with big convex lens before the described plane of incidence, be provided with lenslet behind the described exit facet, the optical axis of described big convex lens and described lenslet overlaps, and focus overlaps to form telescopic system.

5, the pressure beam slice that is used for LCD optic module as claimed in claim 4 is characterized in that described big convex lens are arranged on the described plane of incidence, and described lenslet is arranged on the described exit facet.

6,, it is characterized in that described lenslet is little convex lens as claim 4 or the 5 described pressure beam slices that are used for LCD optic module.

7,, it is characterized in that described lenslet is little concavees lens as claim 4 or the 5 described pressure beam slices that are used for LCD optic module.