CN103322505B - Secondary optical lens for liquid crystal display backlight system - Google Patents

Abstract

The invention discloses a kind of secondary optical lens for liquid crystal display backlight system, including bottom surface and light distribution curved surface, the middle part at described light distribution curved surface top is protruding upward forms projection, the lateral surface of described projection is cylindrical exiting surface, the middle part of described convex top is downwardly concaved formation reflecting surface, it is provided with step in described fully reflecting surface, the upwardly recessed formation in middle part inner groovy from described bottom surface, described inner groovy has side and is positioned at the caustic surface of described side top, described side is the surface of revolution, after the part making incident ray is assembled by described caustic surface, fully reflecting surface described in directive, the lateral surface outgoing by described projection of the light after reflection.This secondary optical lens, uses the method for refraction and total reflection combination to realize the beam angle full-shape luminous intensity distribution more than or equal to 170 °, can further shorten the distance between LED-baseplate and lcd screen, the thickness of back light system is greatly reduced.

Description

Secondary optical lens for liquid crystal display backlight system

Technical field

The present invention is about a kind of secondary optical lens for large-screen lc display backlight system.

Background technology

The LED backlight system of straight-down negative (will be arranged in the photograph illuminating liquid crystal display screen panel directly below of LCD screen by LED Bright system) because its simple in construction, light loss are few, colour developing prime number height, good evenness, LED can arbitrarily arrange, it is multiple to carry out The features such as miscellaneous light guide plate mesh point design, have obtained increasingly being widely applied.Pursue more and more thinner and uniformly illumination be The development trend of the back light system of giant-screen LCD (liquid crystal display), secondary optical lens is the key factor played a decisive role. Although existing major part secondary optical lens can largely reduce the thickness of back light system, but it has one to be difficult to exceed Bottleneck more, in the back light system can accomplished in the market, the height width ratio of the limit of its secondary optical lens is (i.e. from LED The ratio of the substrate distance to lcd screen and LED arrangement pitches) generally about 0.25, it is simply that when LED spacing is 100mm The when of arrangement, need about 25mm from the distance of the substrate of LED to lcd screen, will produce less than 0.25 just to LED position The spot center put is the brightest, thus is difficulty with the Uniform Illumination of lcd screen.

Summary of the invention

It is an object of the invention to for the deficiencies in the prior art, it is provided that a kind of can effectively reduce the two of back light system thickness Secondary optical lens.

For achieving the above object, present invention employs techniques below mode: a kind of secondary optical lens, including bottom surface and from Upwards arch upward the light distribution curved surface formed at the edge of described bottom surface, and the middle part formation protruding upward at described light distribution curved surface top is convex Rising, the lateral surface of described projection is cylindrical exiting surface, and the middle part of described convex top is downwardly concaved formation fully reflecting surface, Being provided with step in described fully reflecting surface, the upwardly recessed formation in the middle part inner groovy from described bottom surface, described inner groovy has Side and be positioned at the caustic surface of described side top, described side is the surface of revolution, makes a part for incident ray by described optically focused After face is assembled, fully reflecting surface described in directive, the lateral surface outgoing by described projection of the light after total reflection；Described incident ray Another part through described inner groovy side reflect after, through described light distribution curved surface outgoing.This secondary optical lens may be used for Liquid crystal display backlight system.

Further, the side of described inner groovy is the circular arc surface of revolution, and the hatching of the described circular arc surface of revolution is circle Arc, all normals of described circular arc all intersect at the summit P of N point, described N point and circular arc in same level.

Further, described cylindrical curved surface is the sweep surface (Sweep Surface) of positive round or non-positive round.

Further, described reflecting surface be coned face, the conical surface of band Fresnel stricture of vagina, section profile line by mini line segment and The ring grain of curve composition be combined the conical surface, on four sides taper surface, polyhedral cone shaped or formed by coned face and polyhedral cone shaped are compound.

Further, the reflection mode of described reflecting surface is total reflection, non-is entirely or partially totally reflected.

Further, the side of described inner groovy and caustic surface wedge angle transition or arc transition.

Further, described light distribution curved surface, with the diffraction surfaces of ring grain micro structure, makes emergent light produce around main emergent ray The low-angle mixed light of life ± Δ θ, described Δ θ is in the range of 2 °～8 °.

Further, described ring grain micro structure is waveform periodic ring grain micro structure, its Wave crest and wave trough value H be 1～ 25 microns, spacing P of ring grain is 0.02～5 millimeter.

Further, described light distribution curved surface be continuous and derivable curved surface, have mixed light effect ring grain diffraction surfaces, have mixed The squamation shape polyhedron curved surface of light action, there is taking turns with cellular composite surface, X and Y-direction section of mixed light effect The ring grain compound curved surface that wide different mixing free form surface, section profile line are made up of mini line segment and curve, cellular multiaspect Body curved surface, Fresnel curved surface, tetragon mixing free form surface, hexagon mixing free form surface, polygon mixing free form surface or Nonaxisymmetrical free form surface.

Further, described light distribution curved surface is mixed by tetragon mixing free form surface, hexagon mixing free form surface, polygon Close free form surface, cellular polyhedron curved surface, Fresnel curved surface, squamation shape curved surface, X and Y-direction section profile different In mixing free form surface, at least two is composited.

Further, described caustic surface is Fresnel ring grain caustic surface, aspheric surface caustic surface or free form surface.

Further, described reflecting surface is attached with translucent resin or colloid, or is attached with opaque medium.

Further, described reflecting surface coats reflectance coating or pastes reflective sheet.

Further, described optical filter is translucent optical filter or nontransparent optical filter.

Further, described bottom surface is 90 degree of V-shaped groove ring grain faces, tetragonal pyramid pyramidal prismatic array surface, hexagon row Taper seat, frosting or the prism of corner cube array of structures face of row.

A kind of LED lens devices for liquid crystal display backlight system, including LED light source, optical filter and described secondary Optical lens, described optical filter is fixed on described step, and described LED light source is positioned at described inner groovy.

Further, described optical filter is combined into one with described secondary optical lens.

A kind of liquid crystal display backlight system, including described LED lens devices.

Further, described LED lens devices has one or more.

A kind of illuminator, including described LED lens devices.

The invention has the beneficial effects as follows: the present invention proposes the secondary optical lens of a kind of LED, use refraction and total reflection group The method closed, can further shorten the distance between LED-baseplate and lcd screen, the thickness of back light system is greatly reduced, Its depth-width ratio can accomplish less than 0.15.

Accompanying drawing explanation

Fig. 1 is the profile of LED lens devices the first detailed description of the invention；

Fig. 2 a～2e is the front view of the first detailed description of the invention, top view, right view, upward view and axonometric chart respectively；

Fig. 3 is the design principle figure of the first detailed description of the invention；

Fig. 4 is the light distribution curved surface luminous intensity distribution schematic diagram to single ray of the secondary optical lens of the first detailed description of the invention；

Fig. 5 is the three-dimensional model diagram of the first detailed description of the invention；

Fig. 6 a, 6b are the ray tracing figures of the first detailed description of the invention；

Fig. 7 is first detailed description of the invention illumination equal pitch contour scattergram in the lcd screen of distance LED-baseplate 15mm；

Fig. 8 is the candela rectangular distribution (distribution curve flux) of the first detailed description of the invention；

Fig. 9 is candela polar coordinate scattergram (distribution curve flux) of the first detailed description of the invention；

Figure 10 a, 10b are the ray tracing figures of the backlight module of the 6*6 array of the first detailed description of the invention, wherein, between LED Away from for 12mm, lcd screen is 15mm from the distance of pcb board, and this ray tracing only demonstrates the light being mapped on screen；

Figure 11 is 6 × 6 arrays of the first detailed description of the invention, and LED spacing is 120mm, the distance of lcd screen to pcb board Illumination Distribution contour map during for 15mm, on screen；

Figure 12 is the design principle figure of the second detailed description of the invention of LED lens devices；

Figure 13 is the candela rectangular distribution of the second detailed description of the invention；

Figure 14 is the candela polar coordinate scattergram of the second detailed description of the invention；

Figure 15 is the profile of the 3rd detailed description of the invention of LED lens devices；

Figure 16 is the design principle figure of the 3rd detailed description of the invention；

Figure 17 is the design principle figure of the 4th detailed description of the invention of LED lens devices；

Figure 18 a～18e is front view, top view, right view, upward view and the solid of the 4th detailed description of the invention respectively Figure；

Figure 19 a～19e be respectively the front view of the 5th detailed description of the invention of LED lens devices, top view, right view, Upward view and axonometric chart；

Figure 20 is the mixed light schematic diagram of the 5th detailed description of the invention of LED lens devices；

Figure 21 a, 21b are profile and the upward view of the 6th detailed description of the invention of LED lens devices respectively；

Figure 22 a, 22b are profile and the upward view of the 7th detailed description of the invention of LED lens devices respectively；

Figure 23 a～23d is the 8th～11 poplar views of secondary optical lens of detailed description of the invention respectively.

Detailed description of the invention

Combine accompanying drawing below by detailed description of the invention the present invention is described in further detail.

First detailed description of the invention of LED lens devices involved in the present invention, the profile of this lens devices such as Fig. 1 institute Showing, the front view of the lens involved by this embodiment, axonometric chart, top view, right view and upward view are as shown in Figure 2.Should Lens devices includes LED light source, secondary optical lens 1 and optical filter 2.The feature of described secondary optical lens 1 is: under lens Side is equipped with an inner groovy near the interposition of LED light source, and the side 11 of inner groovy is that (i.e. its hatching is circle to the circular arc surface of revolution Arc), the end face 13 of inner groovy is an aspheric surface caustic surface；A cylindrical bump, protruding interposition is had to be equipped with one above lens Toward the conical reflecting surface 14 of lower recess, it having the step 16 for placing optical filter, protruding lateral surface 15 is for somewhat to have The cylindrical curved surface as exiting surface of some gradient；The side, outer ring 12 of secondary optical lens is also exiting surface, and it plays luminous intensity distribution effect, It is the curved surface of continuous and derivable；The bottom surface 17 of secondary optical lens is Non-optical surfaces, has according to hexagonal array above it It is used for collecting the retro-reflection miniature prism of corner cube face 18 of veiling glare.Additionally the bottom of secondary optical lens can also be used for fixing Card base 19, its be used for these lens are fixed on the circuit board of LED.The optical filter 2 of the illuminator of described LED, it is placed In the step 16 that lens upper cylindrical shape is protruding, it can be the translucent film of milky, or the scattering of frosted finish effect Sheet, or alternatively coating and the sheet material of coating.The LED that the illuminator of described LED uses, it can be various lambert The LED of shape distribution.

The reflection mode of the surface of emission can be total reflection, non-entirely or partially be totally reflected.Protruding lateral surface is cylindricality Curved surface, this cylindrical curved surface can be positive round or the sweep surface of non-positive round, and its a kind of shape is cylindrical surface or with withdrawing pattern The cylindrical surface of gradient.Reflecting surface can be coned face, the conical surface of band Fresnel stricture of vagina, section profile line by mini line segment and The ring grain of curve composition be combined the conical surface, on four sides taper surface, polyhedral cone shaped or formed by coned face and polyhedral cone shaped are compound.

Light distribution curved surface can be the curved surface of continuous and derivable, have the ring grain diffraction surfaces of mixed light effect, has mixed light effect Squamation shape polyhedron curved surface, there are the different with cellular composite surface, X and Y-direction section profile of mixed light effect The ring grain compound curved surface that mixing free form surface, section profile line are made up of mini line segment and curve, cellular polyhedron curved surface, phenanthrene Nie Er curved surface, tetragon mixing free form surface, hexagon mixing free form surface, polygon mixing free form surface or nonaxisymmetrical Free form surface.

Light distribution curved surface can also by tetragon mixing free form surface, hexagon mixing free form surface, polygon mixing freely The different mixing of curved surface, cellular polyhedron curved surface, Fresnel curved surface, squamation shape curved surface, X and Y-direction section profile from It is composited by least two in curved surface.

Caustic surface can be Fresnel ring grain caustic surface, aspheric surface caustic surface or free form surface.

Translucent resin or colloid can be attached with on reflecting surface, or be attached with opaque medium.

Reflecting surface can coat reflectance coating or paste reflective sheet.

Optical filter can be translucent optical filter or nontransparent optical filter.

Fig. 3 is the design principle figure of the first detailed description of the invention.From the light of LED light source light-emitting area central point O injection, its The light of mid portion is assembled by aspheric end face 13, after convergence on the directive conical fully reflecting surface 14 above it, and reflection After light penetrated by cylindrical outer side face 15, all of emergent ray and optical axis OZ are θ_maxAngle, θ_max85 °～90 ° it Between, the most preferably 85 °.Being molded for convenience, the lateral surface top in cylindrical outer side face 15 is slightly thin, the thickest, somewhat has Some pattern drafts, withdrawing pattern oblique angle between 1 °～5 °, the most preferably 2 °.Remaining from the injection of LED light source light-emitting area center O point The light of lateral parts, after reflecting for the side 11 of the circular arc surface of revolution, incide the light distribution curved surface 12 outside lens On, from the light of light distribution curved surface 12 outgoing, from top to bottom, it is evenly distributed in 0～θ respectively with the angle of optical axis OZ_maxAngle it Between, θ_maxBetween 85 °～90 °, the most preferably also 85 °.The described side 11 for the circular arc surface of revolution, its hatching is Circular arc, its all normals all intersect at the summit P of N point, N point and circular arc in same level.When fluorescent powder coated of LED is bigger Time, have some light and spill from the taper seat fully reflecting surface 14 of lensed tip, emergent light spot forms the ring of light, the most thereon Side placed a tablet filter 2, and it is translucent milky film or the diffusion sheet of band frosted, is used for beating veiling glare Dissipate, eliminate the ring of light, it is possible to stop veiling glare by plated film on the taper seat reflecting surface of lensed tip or applying coating and eliminate light Ring, makes the distribution of the uniform light that forming range is bigger.It addition, when fluorescent powder coated of LED bigger, also can some veiling glare Can be reflected toward the lower section of lens by light distribution curved surface 12, devise the miniature angle according to hexagonal array at lens base the most here The retro-reflection face of cone prism array, is used for collecting veiling glare, and toward the top reflection of lens.

Fig. 4 is the light distribution curved surface 12 luminous intensity distribution figure to single ray QR, its light distribution angle (emergent ray and the folder of optical axis OZ Angle) meet following tangent condition:

$\mathrm{\θ}={\tan }^{-1}(\frac{\mathrm{\γ}-\mathrm{\β}}{90-\mathrm{\β}}\·\tan {\mathrm{\θ}}_{\max })$

(X, Y) coordinate figure of the contour line of light distribution curved surface 12, according to above-mentioned formula, is calculated by iterative Integral Method.Optically focused top Face 13 then can be gone out by imaging design software optimization.The three of secondary optical lens are formed by calculating and optimizing each curved surface out Dimension physical model, as shown in Figure 5.

It is input to the three-dimensional entity model of the secondary optical lens of this detailed description of the invention in photometric analysis software carry out Ray tracing and computer simulation.Assume the Luxeon Rebel White that model is PHILIPS Co. of LED light source Display LED, luminous flux is 90 lumens, and the height of the lcd screen distance LED-baseplate of required illumination is 15mm, on lens The optical characteristics of the optical filter 2 of side is scattering white (Diffuse White), can bright according in the middle of hot spot on screen in reality Secretly and whether have the situation regulation transparency of optical filter and the frosted degree of the ring of light.Fig. 6 is the light of the first detailed description of the invention Trace figure.Fig. 7 is the illuminance equal pitch contour scattergram on screen, it can be seen that the diameter range of hot spot has exceeded 200mm.First Far field angle distribution (distribution curve flux) of the light intensity of detailed description of the invention, as can be seen from figures 8 and 9, Fig. 8 is candela rectangular coordinate Scattergram, Fig. 9 is candela polar coordinate scattergram, it can be seen that major part light distribution is between ± 75 °～± 90 °, and it is The position of big light intensity value is at about ± 85 °, and the ratio of the light intensity value within mid portion ± 65 ° is relatively low and smooth, and its value is about The 3.5% of big light intensity value, this some light is mainly used to illuminate on screen just to the position above LED.

Figure 10 is the ray tracing figure of the backlight module of 6 × 6 arrays of the first detailed description of the invention, and LED spacing is 120mm, the lcd screen of required illumination is 15mm from the distance of pcb board, the most only shows the light being mapped on screen.In figure Less black lines is the light from secondary optical lens injection, and the luminous intensity distribution of this lens area just above is adjacent saturating from it The light that lens device is penetrated, so that reaching the irradiation of uniform-illumination.Figure 11 is the Illumination Distribution contour map on screen, permissible Finding out the maximum about 6500Lux (lux) of Illumination Distribution, the minimum of Illumination Distribution is about 5500Lux, can obtain on screen Illumination Distribution the uniformity be about:

$\mathrm{\η}\≈\frac{5500\mathrm{Lux}}{6500\mathrm{Lux}}\·100\%=84.6\%$

Figure 10 is the ray tracing figure of the backlight module of 6 × 6 arrays of the first detailed description of the invention, and LED spacing is 120mm, screen is 15mm from the distance of pcb board, and this ray tracing figure only demonstrates the light being mapped on screen.

Second detailed description of the invention:

In second detailed description of the invention, except the light distribution curved surface 122 of secondary optical lens lateral surface is embodied as with first Outside mode is different, other structures are all essentially identical with the first detailed description of the invention.The design of the second detailed description of the invention is former As shown in figure 12, its all output light through light distribution curved surface 122 luminous intensity distribution, it is all θ with the angle of optical axis to reason_max, and concrete Through the output light of light distribution curved surface 12 luminous intensity distribution in embodiment, it is evenly distributed in 0～θ with the angle of optical axis OZ_maxAngle it Between, θ here_maxPreferably also 85 °.In shape, the curved surface 122 of the second detailed description of the invention is more flat, and first is concrete real Execute the place that the light distribution curved surface 12 of mode is connected with lens upper cylindrical shape lateral surface 15 and appear to have an arc being similar to fillet Shape face.

Second detailed description of the invention has broader range of exposures than the first detailed description of the invention, when LED spacing is 150mm Time, the Illumination Distribution uniformity in lcd screen that distance pcb board 15mm is high can be more than 80%.Second detailed description of the invention As shown in FIG. 13 and 14, Figure 13 is the distribution of candela rectangular coordinate to far field angle distribution (distribution curve flux) of light intensity, Tu14Wei Candela polar coordinate be distributed, it can be seen that major part light distribution between ± 75 °～± 90 °, the position of its largest light intensity value At about ± 85 °, the light intensity value within centre ± 65 ° of scopes is lower than the first detailed description of the invention, the light intensity value of Partial angle Close to 0.

3rd detailed description of the invention:

3rd detailed description of the invention of secondary optical lens involved in the present invention, its profile is as shown in figure 15.With Unlike one detailed description of the invention, the side 113 of the female parts in the centre position of close LED below lens, it is the conical surface. Other methods for designing of several are then identical with the first detailed description of the invention, and the end face 133 including indent is an aspheric surface optically focused Face；Having a cylindrical bump above lens, protruding interposition is equipped with one toward the conical fully reflecting surface 143 of lower recess, on it There are the step 163 for placing optical filter, the protruding cylindrical exiting surface that lateral surface 153 is somewhat gradient；Lens Side, outer ring 123 is also exiting surface, and it plays luminous intensity distribution effect, and it is the curved surface of continuous and derivable；The bottom surface 173 of lens is non-optical table Face, have above it according to hexagonal array for collecting the retro-reflection of veiling glare miniature prism of corner cube face 183 etc..Additionally lens Bottom can also have the card base 193 being used for fixing, its be used for lens are fixed on the circuit board of LED.The illumination of described LED The optical filter 2 of device, it is positioned in the step 163 that lens upper cylindrical shape is protruding, and it can be the translucent glue of milky Sheet, or the diffusion sheet of frosted finish effect, or alternatively coating and the sheet material of coating.The LED that described Optical devices use, It can be the LED of various lambert's shape distribution.

The design principle of the 3rd detailed description of the invention is similar with detailed description of the invention 1.As shown in figure 16, send out from LED chip The light of bright finish central point O injection, the light of intermediate portion assembled by aspheric surface end face 133, and after convergence, directive is above it On taper fully reflecting surface 143, the light after reflection is penetrated by cylindrical outer side face 153, all of emergent ray and optical axis OZ In θ_maxAngle, θ_maxBetween 85 °～90 °, the most preferably 85 °.Being molded for convenience, the top in cylindrical outer side face 153 is slightly Carefully, below the thickest, somewhat have some pattern drafts, withdrawing pattern oblique angle between 1 °～5 °, the most preferably 2 °.Remaining from LED core The light of the lateral parts of sheet light-emitting area center O point injection, incides the luminous intensity distribution outside lens after tapered side 113 reflects On curved surface 123, from the light of light distribution curved surface 123 outgoing, from top to bottom, it is evenly distributed in 0～θ with the angle of optical axis OZ_max Between angle, θ_maxBetween 85 °～90 °, the most preferably also 85 °.

4th detailed description of the invention:

When fluorescent powder coated on LED light source must be diluter, when surface covered is relatively large, use first～three concrete real Execute the secondary optical lens described in mode and LED emergent light is carried out luminous intensity distribution, owing to light distribution angle is the biggest, it is possible on screen The inconsistent situation that in the middle of hot spot, colour temperature is high, hot spot edge colour temperature is low can be produced, thus cause the color uniformity of lcd screen Bad.4th detailed description of the invention of the present invention proposes the solution for this situation.

The profile of the 4th detailed description of the invention as shown in figure 17, in addition to the curved surface 124 in outside, other all of spy Levy all as the first detailed description of the invention, here the light distribution curved surface 124 in outside is designed to the diffraction with ring grain micro structure Face, makes emergent light around the low-angle mixed light of main emergent ray QR generation ± Δ θ, can improve the difference of colour temperature.General next Say Δ θ in the range of 2 °～5 °, the most preferably 3 °.Ring grain micro structure described here is preferably the periodic ring grain of waveform Micro structure, its Wave crest and wave trough value H is 8 microns, and spacing P of ring grain is 0.5 millimeter.Described chief ray QR, its light distribution angle (goes out Penetrate the angle of light and optical axis OZ) also meet following tangent condition:

$\mathrm{\θ}={\tan }^{-1}(\frac{\mathrm{\γ}-\mathrm{\β}}{90-\mathrm{\β}}\·\tan {\mathrm{\θ}}_{\max })$

Plus described ring grain micro structure in outside light distribution curved surface 124, it can produce the mixed light of about ± 3 °, thus solve The problem that certainly in LCD, color temperature difference is different.The 4th described detailed description of the invention, the light distribution curved surface in outside is except corrugated ring Outside stricture of vagina diffraction surfaces, its ring grain face can also being made up of small straightway for section profile line, it is also possible to play good Light mixing effect in low-angle.

Figure 18 is the 3-D view of the 4th involved detailed description of the invention, and the bottom surface 174 of lens is also with for collecting The prism of corner cube type retro-reflection micro structure face 184 of veiling glare, lens outside curve 124 is the diffraction surfaces of ring grain micro structure.

5th detailed description of the invention:

It addition, for likely producing on screen that colour temperature in the middle of hot spot is high, that hot spot edge colour temperature is low is inconsistent The light mixing method of situation, in addition to using the method for the 4th detailed description of the invention, it is also possible to become flakey many lateral layout The method of face body, carries out the mixed light in low-angle.Figure 19 is that the front view of this detailed description of the invention, axonometric chart, top view, the right side regard Figure and upward view.In figure in addition to the light distribution curved surface 125 in outside is according to the flakey polyhedron of hexagonal array, its The design of his curved surface is all identical with the first detailed description of the invention.

Figure 20 is the mixed light schematic diagram of the 5th detailed description of the invention, and Q1Q2 is the section profile line of one of them scale, light Line follows the first detailed description of the invention or the second specific embodiment party through the central point Q of this scale, the light distribution angle of output light The light distributing method of formula.Owing to involved scale is plane, light is through lower edges Q1 and Q2 of scale, and it is around chief ray QR has a least angle of divergence ± Δ θ, and it can play the effect of mixed light with adjacent scale divergent beams out.The most excellent The size selecting each scale makes it, and poor with the section profile line of the first detailed description of the invention rise in corresponding position to be about 8 micro- Rice, thus produce the mixed light of about ± 3 °, thus solve the problem that color temperature difference in LCD is different.

The additionally flakey polyhedron light distribution curved surface 125 described in present embodiment, its can also be according to tetragon or its The flakey polyhedron of his shaped formation.

6th detailed description of the invention:

The secondary optical lens of LED lens devices involved in the present invention, near the interposition of LED light source below its lens The end face of the indent put is also designed to Fresnel (Fresnel) ring grain caustic surface.

Figure 21 is profile and the upward view of described 6th detailed description of the invention, by the first detailed description of the invention in figure The aspherical condenser at female parts top becomes Fresnel lens, optics aspect its as aspherical condenser rise To the effect of optically focused, and configuration aspects its can reduce the space of lens, thus use this structure can be by the size of lens That designs is smaller.

7th detailed description of the invention:

The secondary optical lens of LED lens devices involved in the present invention, other method is middle indent above its lens Reflecting surface on fill or arrange the object of optical characteristics different from lens, this object can be resin or the colloid of semi-transparent shape, Can also be the object with coating or coating, or opaque object.

Figure 22 is profile and the upward view of described 7th detailed description of the invention, by the first detailed description of the invention in figure, Above lens, the diffusion sheet on reflecting surface becomes filling object, equally realizes stopping veiling glare and eliminating the function of the ring of light, from And make the distribution of the uniform illumination that forming range is bigger.

Other detailed description of the invention:

The Optical devices of the described LED backlight system shown for large-screen lc, its described secondary optical lens Bottom be Non-optical surfaces, it can be any surface, can do any process above, including common machine machined surface, frosted Face, it is used for collecting the retro-reflection micro structure face etc. of veiling glare.

The bottom surface of Figure 23 a～23d respectively secondary optical lens is miniature 90 degree of V-flute profile ring grain faces 187, miniature 4 side's cones Pyramidal prismatic array surface 188, the taper seat 189 of miniature 6 limit shape arrangements and frosting 1810, specific embodiment party in figure Formula eight, nine, ten bottom surface is all miniature prism of corner cube array of structures face, and the luminous reflectance inciding lens base can be returned to by it Mirror front.The bottom surface of the secondary optical lens of detailed description of the invention 11 is frosting, and the veiling glare at directive lens rear is beaten by it Dissipate, and the front of partially reflective time lens, if the paint of its white laid on, then the effect collecting veiling glare can be more preferably.

The present invention relates to the Optical devices of a kind of LED backlight system shown for large-screen lc, its feature is this dress Put and be made up of LED light source, secondary optical lens and optical filter.The secondary optical lens of described device, is characterized by: lens Lower section is equipped with an inner groovy near the interposition of LED, and the side of inner groovy is the circular arc surface of revolution or the cone surface of revolution, indent End face be an aspheric surface or for Fresnel (Fresnel) caustic surface；A cylindrical bump, protruding interposition is had above lens Being equipped with one toward the conical fully reflecting surface of lower recess, it has the step for placing optical filter, protruding lateral surface is somewhat There is the cylindrical exiting surface of a gradient；The side, outer ring of lens is also exiting surface, and it is light distribution curved surface, and it can be continuous and derivable Curved surface, it is also possible to for the ring grain being somewhat made up of small straightway with the ring grain diffraction surfaces of mixed light effect, section profile line Face or be polyhedron scale face；The bottom surface of lens is Non-optical surfaces, and it can be any surface, can do any above Process, including common machine machined surface, frosting, for collecting the retro-reflection micro structure face etc. of veiling glare.The additionally bottom of lens Can also there is the card base being used for fixing, can have different shape, size and positions as required, be used for being fixed on lens On the circuit board of LED.The optical filter of the illuminator of described LED, it is positioned in the step that lens upper cylindrical shape is protruding, its Can be the translucent film of milky, or the diffusion sheet of frosted finish effect, or there is the optical filter with site, or also It can be the sheet material of coating and coating.The LED that the illuminator of described LED uses, it can be the distribution of various lambert's shape LED。

Below secondary optical lens, the side 11 of the indent of close LED can be the circular arc surface of revolution, and its hatching is circle Arc, its all normals all intersect at the summit P of N point, N point and circular arc line in same level.

The design principle of secondary optical lens can be, from the light of LED chip light-emitting area central point O injection, in the middle of it The light of part is assembled by aspheric surface end face 13, after convergence on directive taper fully reflecting surface 14 above it, and the light after reflection Being penetrated by cylindrical outer side face 15, all of emergent ray and optical axis OZ are θ_maxAngle, θ_maxBetween 85 °～90 °.For side Just being molded, the top in cylindrical outer side face 15 is slightly thin, the thickest, somewhat has some pattern drafts, and withdrawing pattern oblique angle is at 1 °～5 ° Between.The light of the remaining lateral parts from the injection of LED chip light-emitting area center O point, through the side 11 for the arc surface of revolution Incide in the light distribution curved surface 12 outside lens after refraction, from the light of light distribution curved surface 12 outgoing, from top to bottom, itself and optical axis OZ Angle be evenly distributed in 0～θ_maxBetween angle, θ_maxBetween 85 °～90 °.Outside light distribution curved surface 12 is to single ray QR's Light distributing method, its light distribution angle angle of optical axis OZ (emergent ray with) meets following tangent condition:

$\mathrm{\θ}={\tan }^{-1}(\frac{\mathrm{\γ}-\mathrm{\β}}{90-\mathrm{\β}}\·\tan {\mathrm{\θ}}_{\max })$

Whether the optical characteristics of the optical filter 2 above secondary optical lens can according to the light and shade in the middle of actual hot spot and Having transparency and the frosted degree of the luminous intensity distribution situation regulation optical filter of the ring of light, it can also be the optical filter with site, or It it is the sheet material of coating and coating.

Secondary optical lens interposition raised above is equipped with the conical fully reflecting surface of the past lower recess of, this indent Reflecting surface can also be cambered surface or plane, also can be with one or more layers reflected coat layer or coating on its reflecting surface, it is also possible to For the micro structure with site or ring grain.

Described lens devices, its all output light through light distribution curved surface 122 luminous intensity distribution, its angle with optical axis also may be used With all as θ_max。

Described lens devices, the side of the female parts in the centre position of close LED below its secondary optical lens 113, it is also possible to for taper seat.

Described lens devices, is directed to when the fluorescent powder coated of LED chip must be diluter, and surface covered is relatively large Time, owing to light distribution angle is the biggest, it is possible to colour temperature height, low the differing of colour temperature of hot spot edge in the middle of hot spot can be produced on screen Situation about causing.For this situation, the outside light distribution curved surface 124 of described secondary optical lens can be designed to ring grain The diffraction surfaces of micro structure, makes emergent light around the low-angle mixed light of main emergent ray QR generation ± Δ θ, can improve colour temperature Difference, Δ θ is in the range of 2 °～5 °.

Described lens devices, the inconsistent situation high for colour temperature in the middle of hot spot, hot spot edge colour temperature is low, can be by The outside light distribution curved surface 124 of described secondary optical lens is designed to the ring grain face that section profile line is made up of small straightway.

Described lens devices, the inconsistent situation high for colour temperature in the middle of hot spot, hot spot edge colour temperature is low, can be by Light distribution curved surface 125 outside lens is designed to the polyhedral light distribution curved surface of flakey, its can also be according to tetragon or other The flakey polyhedron of shaped formation, light is through edge Q1 and Q2 of scale, and it has the least dissipating around chief ray QR Angle ± Δ θ, it can play the effect of mixed light with adjacent scale diverging light out.

Described lens devices, below its secondary optical lens, the end face of the indent of close LED can also be Fresnel (Fresnel) ring grain caustic surface.It plays the effect of optically focused as aspherical condenser, and configuration aspects its can reduce The space of lens, thus use this structure can smaller by lens design.

Described lens devices, the Optical devices of this LED backlight system are applied on backlight illuminating system, can be different Spacing is arranged, it is also possible to the different modes spread configuration of single or many.

Described lens devices, can apply in the illuminator in addition to LCD backlight.

Described lens devices, the Optical devices of this LED backlight system are applied on backlight illuminating system, and its lens are just The luminous intensity distribution of top irradiation area is from the light being adjacent lens devices injection.

Described lens devices, its secondary optical lens 1 and the optical filter 2 above it can be integrated combination type and arrange, also It can be split type setting.

Described lens devices, its secondary optical lens 1 can also be that two kinds of different optics are special from the optical filter 2 above it Property material combination or be molded into one.

Described lens devices, the bottom surface of its secondary optical lens is Non-optical surfaces, its can be common machine machined surface, Frosting, it is used for collecting the retro-reflection micro structure face etc. of veiling glare.Described interflection micro structure face, it can be miniature 90 degree V-grooved ring stricture of vagina face 187, miniature 4 side's cone pyramidal prismatic array surface 188, the taper seat 189 of miniature 6 limit shape arrangements, it is permissible The luminous reflectance inciding lens base is returned to lens front.Described frosting, it can be by the veiling glare at directive lens rear Break up, and the front of partially reflective time lens, can be with the paint of coated white on frosting.

Above content is to combine specific embodiment further description made for the present invention, it is impossible to assert this Bright being embodied as is confined to these explanations.For general technical staff of the technical field of the invention, do not taking off On the premise of present inventive concept, it is also possible to make some simple deduction or replace, all should be considered as belonging to the protection of the present invention Scope.

Claims (20)

1. a secondary optical lens, including bottom surface and the light distribution curved surface formed that upwards arches upward from the edge of described bottom surface, it is special Levy and be: the middle part at described light distribution curved surface top is protruding upward forms projection, and the lateral surface of described projection is for as going out light The cylindrical curved surface in face, the middle part of described convex top is downwardly concaved formation reflecting surface, is provided with step in described reflecting surface, from The upwardly recessed formation in the middle part inner groovy of described bottom surface, described inner groovy has side and is positioned at the poly-of described side top Bright finish, described side is the surface of revolution, after making a part for incident ray be assembled by described caustic surface, reflecting surface described in directive, instead The lateral surface outgoing by described projection of the light after penetrating；Another part of described incident ray is rolled over through the side of described inner groovy After penetrating, through described light distribution curved surface outgoing, all of emergent ray and optical axis are θ_maxAngle, θ_maxBetween 85 °～90 °；Described poly- Bright finish indent.

2. secondary optical lens as claimed in claim 1, it is characterised in that: the side of described inner groovy is circular arc revolution Face, the hatching of the described circular arc surface of revolution is circular arc, and all normals of described circular arc all intersect at N point, described N point and circular arc Summit P in same level.

3. secondary optical lens as claimed in claim 1, it is characterised in that: the side of described inner groovy is circular arc revolution Face, section are surface of revolution or the conical surface of non-positive round.

4. secondary optical lens as claimed in claim 1, it is characterised in that: the cylindrical curved surface of described projection is positive round or anon-normal The sweep surface of circle.

5. secondary optical lens as claimed in claim 1, it is characterised in that: described reflecting surface is coned face, band Fresnel The ring grain that the conical surface of stricture of vagina, section profile line are made up of mini line segment and curve be combined the conical surface, on four sides taper surface, polyhedral cone shaped or Formed by coned face and polyhedral cone shaped are compound.

6. secondary optical lens as claimed in claim 1, it is characterised in that: the reflection mode of described reflecting surface is for being all-trans Penetrate, non-be entirely or partially totally reflected.

7. secondary optical lens as claimed in claim 1, it is characterised in that: the side of described inner groovy and caustic surface wedge angle mistake Cross or arc transition.

8. secondary optical lens as claimed in claim 1, it is characterised in that: described light distribution curved surface is spread out with ring grain micro structure Penetrating face, make emergent light produce the ± low-angle mixed light of Δ θ around main emergent ray, described Δ θ is in the range of 2 °～8 °.

9. secondary optical lens as claimed in claim 8, it is characterised in that: described ring grain micro structure is that waveform is periodic Ring grain micro structure, its Wave crest and wave trough value H is 1～25 micron, and spacing P of ring grain is 0.02～5 millimeter.

10. secondary optical lens as claimed in claim 1, it is characterised in that: described light distribution curved surface be continuous and derivable curved surface, The ring grain diffraction surfaces with mixed light effect, the squamation shape polyhedron curved surface with mixed light effect, the band with mixed light effect There are the different mixing free form surface of cellular composite surface, X and Y-direction section profile, section profile line by mini line segment and song The ring grain compound curved surface of line composition, cellular polyhedron curved surface, Fresnel curved surface, tetragon mixing free form surface, hexagon mix Close the one in free form surface and nonaxisymmetrical free form surface.

11. secondary optical lens as claimed in claim 1, it is characterised in that: described light distribution curved surface is by tetragon mixing freely Curved surface, hexagon mixing free form surface, cellular polyhedron curved surface, Fresnel curved surface, squamation shape curved surface, X and Y-direction are cutd open In the mixing free form surface that facial contour is different, at least two is composited.

12. secondary optical lens as claimed in claim 1, it is characterised in that: described caustic surface be Fresnel ring grain caustic surface, Aspheric surface caustic surface or free form surface.

13. secondary optical lens as claimed in claim 1, it is characterised in that: it is attached with translucent tree on described reflecting surface Fat or colloid, or it is attached with opaque medium.

14. secondary optical lens as claimed in claim 1, it is characterised in that: described reflecting surface coats reflectance coating or pastes anti- Penetrate sheet material.

15. secondary optical lens as claimed in claim 1, it is characterised in that: described bottom surface be 90 degree of V-shaped groove ring grain faces, four Side's cone pyramidal prismatic array surface, the taper seat of hexagonal array, frosting or prism of corner cube array of structures face.

16. 1 kinds of LED lens devices for liquid crystal display backlight system, including LED light source, it is characterised in that: also include filter Secondary optical lens described in any one in mating plate and claim 1-15, described optical filter is fixed on described step, institute State LED light source and be positioned at described inner groovy.

17. LED lens devices as claimed in claim 16, it is characterised in that: described optical filter and described secondary optical lens It is combined into one.

18. 1 kinds of liquid crystal display backlight system, it is characterised in that: include the LED lens devices described in claim 17.

19. liquid crystal display backlight system as claimed in claim 18, it is characterised in that: described LED lens devices have one or Multiple.

20. 1 kinds of illuminators, it is characterised in that: include the LED lens devices described in claim 17.