Abstract
We propose an optical design process that significantly reduces the time and costs in direct backlight unit (BLU) development. In it, the basic system specifications are derived from the optical characteristics of RGB light-emitting diodes (LEDs) comprising the BLU. The driving currents are estimated to determine the theoretical RGB flux ratio for a desired white point. The number of LEDs needed to produce the target luminance is then calculated from the combined optical efficiencies of the components. Last, an appropriate array configuration is sought based on the illuminance distribution function for meeting the target uniformity. To showcase the design process we built two 42-inch triangular cluster arrays of 40 × 16 LED elements. When a flat reflective sheet was used, the minimum thickness required of the system to satisfy the target uniformity was 30 mm. Introducing a patterned reflective sheet removed hotspots that resulted from reducing the system thickness without the aid of additional optical components. Using an optimized patterned reflective sheet, reduction in system thickness as much as 5 mm was possible.
| Original language | English |
|---|---|
| Pages (from-to) | 8595-8604 |
| Number of pages | 10 |
| Journal | Optics Express |
| Volume | 18 |
| Issue number | 8 |
| DOIs | |
| Publication status | Published - 2010 Apr 12 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
Cite this
}
Eliminating hotspots in a multi-chip LED array direct backlight system with optimal patterned reflectors for uniform illuminance and minimal system thickness. / Kim, Byungwook; Kim, Joongeok; Ohm, Won Suk; Kang, Shinill.
In: Optics Express, Vol. 18, No. 8, 12.04.2010, p. 8595-8604.Research output: Contribution to journal › Article
TY - JOUR
T1 - Eliminating hotspots in a multi-chip LED array direct backlight system with optimal patterned reflectors for uniform illuminance and minimal system thickness
AU - Kim, Byungwook
AU - Kim, Joongeok
AU - Ohm, Won Suk
AU - Kang, Shinill
PY - 2010/4/12
Y1 - 2010/4/12
N2 - We propose an optical design process that significantly reduces the time and costs in direct backlight unit (BLU) development. In it, the basic system specifications are derived from the optical characteristics of RGB light-emitting diodes (LEDs) comprising the BLU. The driving currents are estimated to determine the theoretical RGB flux ratio for a desired white point. The number of LEDs needed to produce the target luminance is then calculated from the combined optical efficiencies of the components. Last, an appropriate array configuration is sought based on the illuminance distribution function for meeting the target uniformity. To showcase the design process we built two 42-inch triangular cluster arrays of 40 × 16 LED elements. When a flat reflective sheet was used, the minimum thickness required of the system to satisfy the target uniformity was 30 mm. Introducing a patterned reflective sheet removed hotspots that resulted from reducing the system thickness without the aid of additional optical components. Using an optimized patterned reflective sheet, reduction in system thickness as much as 5 mm was possible.
AB - We propose an optical design process that significantly reduces the time and costs in direct backlight unit (BLU) development. In it, the basic system specifications are derived from the optical characteristics of RGB light-emitting diodes (LEDs) comprising the BLU. The driving currents are estimated to determine the theoretical RGB flux ratio for a desired white point. The number of LEDs needed to produce the target luminance is then calculated from the combined optical efficiencies of the components. Last, an appropriate array configuration is sought based on the illuminance distribution function for meeting the target uniformity. To showcase the design process we built two 42-inch triangular cluster arrays of 40 × 16 LED elements. When a flat reflective sheet was used, the minimum thickness required of the system to satisfy the target uniformity was 30 mm. Introducing a patterned reflective sheet removed hotspots that resulted from reducing the system thickness without the aid of additional optical components. Using an optimized patterned reflective sheet, reduction in system thickness as much as 5 mm was possible.
UR - http://www.scopus.com/inward/record.url?scp=77950878411&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77950878411&partnerID=8YFLogxK
U2 - 10.1364/OE.18.008595
DO - 10.1364/OE.18.008595
M3 - Article
C2 - 20588704
AN - SCOPUS:77950878411
VL - 18
SP - 8595
EP - 8604
JO - Optics Express
JF - Optics Express
SN - 1094-4087
IS - 8
ER -