CN201122399Y

CN201122399Y - Outdoor full-color LED large screen display unit

Info

Publication number: CN201122399Y
Application number: CNU2007201250584U
Authority: CN
Inventors: 李志敏; 万睿; 王晓锋; 左熹; 朱小清
Original assignee: Chongqing University
Current assignee: Chongqing University
Priority date: 2007-08-27
Filing date: 2007-08-27
Publication date: 2008-09-24
Anticipated expiration: 2017-08-27

Abstract

The utility model provides an outdoor full color LED large screen display unit, which comprises a unit case body, a circuit board, LED pixel points, a packaged insulating layer and an outdoor reflecting grille cover, etc. Each LED pixel point is formed by combining two red LEDs, two green LEDs and one blue LED. A packaged insulating layer which enables the circuit board to be fully covered to the position of two thirds of the LED is poured on the surface of the circuit board in the unit case body, and the outdoor reflecting grille cover is positioned on the packaged insulating layer. The utility model takes the display unit as an assembly individual, thus being convenient for transportion and assembly; by adopting the 2 to 2 to 1 LED matching ratio, the brightness and the contrast of the large screen are improved, the display effect is improved, and the service life is prolonged; the facade of the LED circuit module is segregated from the outside environment by utilizing the packaged insulating layer, thereby the corrosion degree of the screen body because of outside factors is greatly lowed; the matched outdoor reflecting grille cover effectively reduces the influence of strong light to the direct irradiation of the LEDs, thereby enhancing the display contrast and improving the display effect.

Description

A kind of outdoor all-colour LED large screen display unit

Technical field

The utility model relates to a kind of outdoor all-colour LED large screen display unit that is used for.

Background technology

The LED giant-screen be a kind of be the modern display platform that luminophor is made with LED (light emitting diode), have luminescence efficiency height, long service life, configuration flexibly, characteristics such as rich color and indoor and outdoor surroundings adaptive faculty be strong, be widely used in fields such as finance, traffic, physical culture, advertisement.There is the deficiency of following several respects in the LED giant-screen of Shi Yonging in the market:

On the one hand: according to the display characteristic of all-colour LED giant-screen, by the additive color process principle as can be known, R (redness), G (green), B (blueness) three primary colours are pressed different proportion mix, can synthesize from vain to black versicolor light.Therefore, the all-colour LED giant-screen all is to adopt red LED luminotron, green LED luminotron and blue led luminotron to be used as basic display element.

According to the colorimetry theory, whether white is to weigh LED giant-screen color to show and to be referred to as white balance by a normal basic index.Promptly red brightness is 21% in light, and green brightness is 69%, and blue brightness is 10% o'clock, and what human eye was felt after the colour mixture is pure white.Therefore, in order to reach optimal brightness and least cost, the LED luminotron that should as far as possible select three-color light-emitting intensity to be roughly 3: 6: 1 ratios is formed a pixel.

In the past, because the price of green LED is higher, and human eye is bigger to the color tolerance of green, adopted 2: 1: 1 so LED proportioning at that time, the i.e. pattern of 2 red 1 green 1 indigo plants, for the green composition that shows slightly shortage, most of enterprises all adopt the way that improves green LED voltage (promptly increasing its brightness), thereby realize both having reduced the use (controlling cost) of LED quantity, can satisfy the requirement of white balance and chromatic rendition degree again substantially.

But along with improving constantly of people's appreciation level, and the fast development of LED technology, the price of green LED can be accepted; In addition, the long-term working voltage that improves LED, very big to the influence in its life-span, after green LED lost efficacy in advance (with respect to other two kinds of color LED), the color balance of whole LED display screen will suffer catastrophic collapse, directly cause LED display can not continue to use.Hence one can see that, it is very necessary to break 2: 1: 1 proportionings using for a long time, fully help display effect, and guarantee normal tenure of use of LED display and effectively prolong aspects such as its life-span to consider that it is very urgent to propose new mix proportion scheme from color rendition degree etc.

Second aspect: it is assembled that present LED big screen display screen is to use monolithic led circuit plate to carry out at the scene mostly, very easily causes the damage of led circuit plate in the process of transportation, installation.Therefore, adopt modular display unit, very help production scaleization, product specificationization and the installation of LED enterprise, the convenience of maintenance as LED giant-screen assembling parts.Simultaneously because environment for use complicated and changeable inevitably can be subjected to the influence of extraneous factor, for guaranteeing its long-time steady operation, common safeguard procedures have: waterproof, anticorrosion, lightning protection, windproof, moistureproof, antifreeze, electrostatic prevention etc.According to the regulation of national standard SJ/T 11281-2003 " LED giant-screen method of testing " and GB4208-93 " shell protection grade (IP code) ", outdoor LED giant-screen shell protection is divided into 3 grades, and wherein the A level is minimum, and the C level is the highest, and is as shown in table 1.

Wherein IP33 represents: prevent that diameter from entering, preventing trickle (each vertical plane is trickle in 60 degree scopes, no deleterious effect) greater than the solid foreign materials of 2.5mm;

IP54 represents: dustproof (allowing to enter a limited number of dusts under some rated condition), anti-dabbling (to the shell all directions no deleterious effect that dabbles);

IP66 represents: dirt close (not allowing any dust to enter), anti-strong water spray (to the shell all directions no deleterious effect of spraying water strongly).

The outdoor LED giant-screen of table 1 shell protection grade

	The A level	The B level	The C level
	The A level	The B level	The C level	Outdoor	IP54＞F≥IP33	IP66＞F≥IP54	F≥IP66

This shows, aspect dustproof and waterproof, the LED giant-screen of on-site consolidation obviously exists a lot of defectives and hidden danger, IP66 requirement with reference to the C grade standard, the display unit module of LED giant-screen extremely is necessary to adopt enclosed unit box structure, and use the packaging insulating material that the circuit board upper surface is reached all around and carry out embedding, thereby to greatest extent the pin and the external environment of entire circuit plate and LED luminotron are isolated, avoid various corrosive goodses confrontation screen bodies to work the mischief.

On the other hand, at present, normally used LED pixel surface does not have any attachment device, therefore when sunlight or the irradiation of other ambient light, has apparent in view reflective phenomenon, thereby causes LED giant-screen decrease of contrast, directly influences display effect.

Summary of the invention

The purpose of this utility model provides a kind of and can improve LED large screen display effect for overcoming above-mentioned various shortcoming, and prolongs the outdoor all-colour LED large screen display unit in its serviceable life.

Implementation of the present utility model is as follows:

A kind ofly be used for outdoor all-colour LED large screen display unit, include unit box and polylith and be loaded on its interior led circuit module, the LED pixel that array distribution is arranged on the circuit board of led circuit module, the utility model has at first proposed the proportion design scheme of each LED pixel, and promptly each LED pixel is constituted by two red LED, two green LED and a blue led.Best is that blue led is positioned at LED pixel center, and two red LED and two green LED lie around respectively.

For a long time, the usage ratio of red LED all very big (no matter be 2: 1: 1 or 2: 2: 1, redness is all occupied great proportion), this is because the luminous intensity of red LED is not high, guarantee the brightness and the color balance of whole LED display screen, it is very necessary that this ratio just seems; In addition, the development of red LED the earliest, technology is the most ripe, price is minimum, makes the producer to bear overweight cost pressure for this ratio.

And compare with LED mix proportion scheme (2: 1: 1) commonly used, the proportion design that the utility model proposes (2: 2: 1) improvements are that it meets desired 3: 6: 1 ratios of white balance more.In red, green, blue three looks green extremely important, it has occupied the brightness of white 69%, and is in the center of color transverse row tabulation, and therefore when the purity of balance color and price concerning between the two, green should be the object of considering emphatically.And why directly do not use the standard proportional of white balance, be because human eye is least responsive (with respect to red and blue for the variation of green, green color tolerance maximum), control based on cost is considered, adopt the green LED with red equivalent, be enough to effect with find an equilibrium point in price.

In addition, along with the use of LED giant-screen, the attenuation problem of LED has to draw attention, the red, green, blue three-color LED comparatively speaking, the rate of decay of red LED is the slowest, secondly be green LED, and blue led is the fastest.This shows, after the LED giant-screen uses a period of time, when using the proportioning of 2 red 1 green 1 indigo plants, blue and green LED can be successively because decay and the destruction giant-screen color proportion balance when dispatching from the factory, thereby have a strong impact on the display effect of giant-screen.Thus, as if the ratio that suitably increases blue and green LED very necessary, but in fact human eye is to versicolor resolution and inconsistent, wherein the resolution of blueness is probably had only 1/4 of red, green resolution, and blue led uses and too much can make giant-screen purple partially easily, practical application shows that also blue real image vegetarian refreshments has certain disappearance also smaller to the image effect influence.

Based on above each point, the utility model keeps the blue led constant rate, suitably improve the green LED ratio, adopt 2 red 2 green 1 blue schemes of colour, with the brightness and contrast who very improves outdoor all-colour LED giant-screen effectively, to prolonging the serviceable life of LED giant-screen, it is highly beneficial to improve display effect.

Further, the utility model designs the structures such as water proof and dust proof of display unit, its scheme be irritate at the circuit board upper surface the complete covering board of one deck surface is arranged, and circuit board between, the packaging insulating layer of all slits and LED bottom 2/3 between circuit board and the unit box, the packaging insulating layer is two component normal-temperature curing epoxy potting compounds, is the black solid crystalline lens after the last moulding.This packaging insulating layer makes the display unit front of whole LED giant-screen only have the light-emitting area of LED to contact with external environment.Like this, the globality of strengthening electronic device improves the resistivity to external shock, vibrations significantly; Improve the insulating property between element, the circuit; Avoid element, circuit etc. to be directly exposed in the external environment; Improve abilities such as its waterproof, protection against the tide.

In addition, reflective barrier cover has been installed on the led circuit module in described whole unit casing, and reflective barrier cover is made of substrate and barrier, have on the substrate with the led circuit module on LED pixel cell LED pilot hole one to one, barrier is positioned at LED pilot hole upper edge, perpendicular to substrate.Like this,, can effectively reduce its interference, reduce reflective influence, thereby improve the contrast of giant-screen, and then improve display effect the LED pixel high light being arranged when the irradiation of this direction is come.

Advantage of the present utility model is: with the display unit of the LED giant-screen assembling individuality as outdoor all-colour LED giant-screen, be convenient to transportation and assembling, improved damage resistance; Adopt 2: 2: 1 LED proportioning, improved the brightness and the contrast of giant-screen, improve the display effect of outdoor all-colour LED giant-screen effectively, and prolong the serviceable life of LED; Use the positive and external environment isolation of packaging insulating layer, greatly reduce the workload that the screen body is subjected to the degree of extraneous factor corrosion and has reduced maintenance, prolonged the serviceable life of LED giant-screen the led circuit module; Supporting outdoor reflective barrier cover can effectively reduce the influence of high light to the LED direct irradiation, shows contrast thereby improve, and improves display effect.

Description of drawings

Fig. 1 is whole outdoor all-colour LED large screen display unit structural representation;

Fig. 2 is the Facad structure figure of led circuit module;

Fig. 3 is the enlarged drawing of A portion among Fig. 2;

(a) figure among Fig. 4 is the synoptic diagram before the positive perfusion of the led circuit module packaging insulating layer; (b) figure is the synoptic diagram behind the perfusion packaging insulating layer;

(a) figure is the plane structure chart of reflective barrier cover among Fig. 5; (b) figure is that the A of (a) figure is to view; (c) figure is that the B of (a) figure is to view.

Embodiment

Fig. 1 has shown a kind of structure that is used for outdoor all-colour LED large screen display unit, and it mainly is made of unit box 1, circuit board 2, LED pixel 3, packaging insulating layer 4 and reflective barrier cover 5 etc., and one-piece construction as shown in Figure 1.

Unit box 1 is the aluminum rectangular frame, and rear portion opened has a plurality of supports in order to fixing circuit board 2.The size of casing can design as required, as adopts long 105cm, wide 35cm, and Aspect Ratio is 3: 1 a mode, 6 * 2 totally 12 led circuit modules just can be installed in it, the long 16cm of led circuit module, wide 16cm closely arrange between each piece, are fixed on the antinose-dive leg by screw.

Bottom in the unit box 1 (being more than the support) is a circuit board 2, LED pixel cell 3 is welded on the circuit board 2, LED and circuit board constitute the led circuit module jointly, each module is made of 8 * 8 LED pixels, wherein each pixel by 2 red (R), 2 green (G), 1 indigo plant (B) totally 5 LED constitute, the nut pilot hole 6 that reservation is arranged on the circuit board, as shown in Figures 2 and 3.

Circuit board 2 upper surfaces are irritated the complete covering board of one deck surface, and circuit board and unit box between the packaging insulating layer 4 of all slits and LED pixel 3 bottoms 2/3.LED is welded on the circuit board 2, location card base 7 to LED luminotrons still have the distance about 3mm, shown in (a) figure among Fig. 4,4 thick about 7mm of packaging insulating layer that the packaging insulating potting compound is formed, can very effectively LED be located the complete and external environment isolation of card base and partial L ED luminotron, shown in (b) figure among Fig. 4.Be noted that simultaneously that in order to improve the giant-screen contrast do not cause light to disturb to LED, the packaging insulating layer is a black.

Electronic potting resin principal ingredient as the packaging insulating layer is an epoxy resin, standard code: Q/94050/, and specifications and models: yy-3 is two component normal-temperature curing epoxy potting compounds, need not heat promptly curable, not high to equipment requirements, very easy to use after the embedding.Ultimate principle is: by the liquid-state epoxy resin compound is poured into mechanical or manual mode the surperficial or inner of electronic component, circuit is housed, is solidified into the heat of excellent performance because of the property insulating polymeric material under normal temperature (or heating) condition.From (b) figure of Fig. 4, can see, after pouring into the packaging insulating layer, only having an appointment outside 1/3 LED light-emitting area is exposed in whole LED circuit module front, has improved abilities such as dustproof, waterproof, anticorrosion, windproof, protection against the tide significantly, can very prolong the serviceable life of LED giant-screen effectively.

Outdoor reflective barrier cover 5 is made up of substrate 51 and barrier 52, is installed on the packaging insulating layer 4, by the nut pilot hole of reserving 54, substrate 51 and circuit board 2 can be fixed into one.At each LED pixel, all to a square LED pilot hole 53 should be arranged, on sunniness direction, there is a barrier 52 upper edge of LED pilot hole 53 perpendicular to the substrate design, in order to stop the direct irradiation of light simultaneously on the substrate 51.As (a) figure, (b) figure of Fig. 5 with (c) shown in the figure.

When the barrier cover was installed, each pixel should be corresponding one by one with supporting LED pilot hole, thereby satisfy the LED giant-screen flatness requirement of regulation in " LED giant-screen method of testing " (SJ/T 11281-2003); In addition, all there is a barrier each LED pilot hole upper edge (being sunniness direction), high light is being arranged when the irradiation of this direction is come, can effectively reduce its interference to the LED pixel, reduce reflective influence, thereby improve the contrast of giant-screen, and then improve display effect.

Claims

1, a kind of outdoor all-colour LED large screen display unit, include unit box and polylith and be loaded on its interior led circuit module, the LED pixel of array distribution is arranged on the circuit board of led circuit module, it is characterized in that: each LED pixel is constituted by two red LED, two green LED and a blue led.

2, outdoor all-colour LED large screen display unit according to claim 1, it is characterized in that: the blue led of described LED pixel is positioned at the center, and two red LED and two green LED lie around respectively.

3, outdoor all-colour LED large screen display unit according to claim 1 and 2 is characterized in that: described circuit board upper surface is irritated the complete covering board of one deck surface, and circuit board between, the packaging insulating layer of all slits and LED bottom 2/3 between circuit board and the unit box.

4, outdoor all-colour LED large screen display unit according to claim 3, described packaging insulating layer are two component normal-temperature curing epoxy potting compounds, are the black solid crystalline lens after the last moulding.

5, outdoor all-colour LED large screen display unit according to claim 1 and 2, it is characterized in that: reflective barrier cover is installed on the led circuit module in described whole unit casing, reflective barrier cover is made of substrate and barrier, have on the substrate with the led circuit module on LED pixel cell LED pilot hole one to one, barrier is positioned at LED pilot hole upper edge, perpendicular to substrate.