What’s the environmental brightness requirements to the led screen display ?
Common brightness requirements as below:
(1) indoor: >800CD/M2
(3)outdoor (locate south ,face north) >4000CD/M2
(4)outdoor (locate north ,face south) >8000CD/M2
What’s the brightness requirements of RGB in the white color configuration?
Red, Green, Blue contributes differently in white color quality, the root reason is due to human eyes’ retina. feels different to light that has different wavelength.
Why high level full color display should use pure green tube?
In practical production of LED display, should choose tricolor that has high lighting efficiency and vivid pictures.?
LED lamp, in order to make the area of color triangle as close as possible to color curve in tongue shape in chroma chart in order to meet abundant colors and emit enough brightness, the finial curve in tongue shape is 515nm wavelength light, so, high level LED display choose pure green LED lamp whose wavelength close to 515nm. For example, ?to choose LED lamp which has wavelength 520nm?525nm or 530nm
How to calculate brightness of each lamp under the conditions of definite brightness and pixel density ?
The calculating methods as below: ( for example: 2R,1G, 1B)
Red LED lamp brightness: brightness (CD)/M2÷dots/M2×0.3÷2
Green LED lamp brightness: brightness (CD)/M2÷dots/M2×0.6
Blue LED lamp brightness: brightness (CD)/M2÷dots/M2×0.1
For example: 2500dots/sqm, 2R1G1B, brightness requirement 5000 CD/M2, so:
Red LED lamp brightness: 5000÷2500×0.3÷2=0.3
Green LED lamp brightness: 5000÷2500×0.6÷2=1.2
Blue LED lamp brightness: 5000÷2500×0.1=0.2
Brightness per pixel: 0.3×2+1.2+0.2=2.0 CD
why we choose DVI display connector standard ?
(1)The DVI display connector meets the computer international standard
(2)no need to open cabinet, you can install easily
(3)high memory, display good quality dynamic pictures
(4)strong compatible ability of software and hardware
(5)support all operation system and application software, display neatly and conveniently
(6)Volume-produce, low cost, convenient maintenance
Whether we can use a notebook to control the display or not, why ?
Can’t . the display card of a notebook is inside, can’t realize connection with control system. Now, there is a type of notebook with DVI connector, it can realize notebook control.
What’s the differences between using NICHIA tubes and chinese tubes for full color LED display except prices ?
(1)chips: NICHIA produces chips itself, chinese tubes use USA or Taiwan chips usually.
(2)packaging: NICHIA does packaging itself, there is no manufacturer in China; there are more packaging factory for Chinese tubes?
(3)consistency: difference of chip wavelength is less in the same lot of NICHIA tubes, good consistency; worse consistency in Chinese tubes.
(4)life time: longer life time for NICHIA tubes, serious attenuation for Chinese tubes
What’s the differences between indoor module full color screen and SMD full color screen ?
(1) lighting part: normally, the display module is olivine color for module full color screen, more expensive for pure green module; normally, use pure green chips for SMD full color screen.
(2)display effect : pixels in module full color screen looks wider, lower brightness, easy to cause mosaic phenomenon; better consistency and higher brightness for SMD full color screen.
(3)maintenance: not easy maintenance for module full color, higher cost of replacement of whole module; easy maintenance for SMD full color, cell lamp can be maintained and replaced
Can SMD LED be used in outdoor screen ? Why ?
Can’t . requirements for installation structure of outdoor screen is strict, SMD LED can not adapt to outdoor scurviness environment
High requirements for outdoor screen brightness, at present, SMD LED can’t reach the brightness requirements of outdoor screen
Why the lead time of outdoor screen is longer ?
(1)materials purchase: the purchase term of LED lamps is longer, special imported chips, the lead time takes 4-6 weeks
(2)complicated producing technics : need PCB design, cover making, glue filling, white balance adjust, etc
(3)strict structure requirements: design for cabinet, need to consider windproof, rainproof, lightningproof , etc.
How to help client choose suitable display ?
(1)the needs of displaying content
(2)visible distance,, visual angle confirm
(3) requirements of cabinet resolution
(4)requirements of installation environment