Transcript DLP Projector

DLP Projector
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Agenda
1. What is DMD?
2. DLP projector
- Why should we choice DLP projector?
- Optical configurations
- Optical elements
3. How it works?
- FSC
- SCR
1. What is DMD ?
DMD: Digital Micromirror Device
Beginning to be developed by sight change according to the movement of Rear View Mirror
Number of moving parts - 0.5 (SVGA) to >1.3 (TBA) million
Mechanical motion - - - - - Makes discrete contacts or landings
Lifetime - - - - - - - - - - - - - up to 100,000 hrs
Address voltage - - - - - - - 3.3-volt CMOS technology
Mechanical elements - - - - Aluminum
Process - - - - - - - - - - - - - Low temperature, sputter deposition,
plasma etch (standard SC processes)
Package (Type A) - - - - - - Optical, hermetic, welded lid
Mirror
Address
Electrode
Yoke
Bias/Reset
Bus
Metal
Address
Pads
Tilting Angle: ±10˚ ±12˚
1. What is DMD ?
Expressing light and shade by changes of selected light by path Mirror Tilting
Expressing Gray level by times taken for path change
2. DLP Projector –
Why should we choice DLP projector?
Image Quality
- Pixelization (fill factor)
DLP= ‘Seamless’, Filmlike
LCD= Grainy, Pixellated
DLP™ = large ‘active’ area
LCD = smaller ‘active’ area
- Contrast Ratio
DLP= simple optics: easier light management
LCD= complex optics: more difficult light management
- Sharpness (color alignment)
DLP= no misalignment
LCD= misalignment likely over time
DLP™
LCD
- Video Quality
DLP= fast switching: minimal ‘lag’ (few μs)
LCD= slow switching: significant ‘lag’ (tens of ms)  smearing for fast moving video
2. DLP Projector –
Why should we choice DLP projector?
- Color Quality
DLP= can match any LCD color gamut
LCD= can’t match any DLP color gamut
R,G,B Bandwidth is depend on each color because of non-sequential system
DLPTM
LCD
wavelength
wavelength
- Smallest & Brightest
DLP= simple optical system,
good reflectivity
LCD= complex optical system
DLPTM
LCD
2. DLP Projector –
Why should we choice DLP projector?
Repeatable Performance (digital accuracy)
DLP= digital: precise control, constant performance over time
LCD= analog: variable (affected by temperature, vibration, heat, humidity),
deterioration over time
Reliable
- Superior thermal characteristics
DLP= reflects heat
LCD= absorbs heat, performance degrades
- LCD panel degrades as a function of both time and use
- DMDs have shown consistent robust performance over time with up to 100,000
hours lifetime
Start
LCD
DLP
2. DLP Projector –
Optical configurations
Number of DMD
1 Chip DLP
3 Chip DLP
2. DLP Projector –
Optical Configurations
TIR prism
Non TIR Prism DLP
TIR Prism DLP
2. DLP Projector –
Optical Configurations
TIR prism
Non TIR Prism DLP
TIR Prism DLP
2. DLP Projector –
Optical elements
TIR Prism
(Total Internal Reflection)
DMD Panel
Condenser Lens C3
(Aspherical Surface)
Mirror
Condenser Lens C2
Condenser Lens C1
Integrating Rod
Reflector
(Elliptical Surface)
Lamp
Aperture
Front Glass
(UV Cut Coating)
Color Drum
(R,G,B,W segment)
※Color Wheel
2. DLP Projector –
Optical elements
(1) Lamp & Reflector
a. Output Voltage
- AC Type : PHILIPS, OSRAM, IWASAKI, THOSHIBA ….
- DC Type : USHIO …
b. Reflector
- Elliptical Type : Almost of all DLP Projector
Smallest size= Φ33mm, ‘Bami’ lamp made by Philips
- Parabolic Type : Used with condensor lens . Some of AV Projector
Elliptical Reflector
Parabolic Reflector
2. DLP Projector –
Optical elements
(2) UV Cut Filter
- UV causes heat for some parts . (Coating, Plastic, Bonding)
- On UV Cut Coating, Try not to make the reflected light be concentrated on one point of UV Lamp
UV Cut Filter
100
90
Reflected
UV light
Transmittance(%)
80
70
60
50
40
30
AOI=0 deg
20
AOI=10 deg
10
0
380 400 420 440 460 480 500 520 540 560 580 600 620 640 660 680 700 720 740 760 780
Wavelength(nm)
Material: Borofloat + UV Coating
2. DLP Projector –
Optical elements
(3) Rod Integrator
- through internal reflects, it makes uninformative incident light distribution “rectangular
uninformative light”
Type: Solid Rod – Glass or Plastic
Light Tunnel – Mirror
in
out
Avd: good transmission. Strong against heat
DisAvd: easy to broken, easy to get dust , long
Light Distribution
from the input
Avd: easy to install, dust free, Short
DisAvd: less transmission, weak for heat
Light Distribution
from the output
2. DLP Projector –
Optical elements
(3) Color Drum & Wheel
Optical instrument filtering color by Color Filter assembled with Motor \
< Color Drum >
< Color Wheel >
< SCR Color Drum >
2. DLP Projector –
Optical elements
(4) Illumination Lenses
It guides lights from Rod Integrator into valid dimensions of DMD
L2
L1
(m)= h’ / h
h
h’
θ
θ’
= f2 / f1
(t)= 2*(f1+f2)
f1
f1
f2
f2
t
L2
L1
< JT30 >
R1
R5
R4
f1 = 9.53, f2 = 22.79
※ m = 2.39배
R2 R3
R6
2. DLP Projector –
Optical elements
(5) Mirror
It changes light path or controls light position on DMD
2. DLP Projector –
Optical elements
(5) (TIR Prism)
Using air gaps between two prism, it makes selective reflect of transmission
in
out
out
air gap
in
air gap
<in : reflect, out : transmission>
<in : transmission, out :
Reflect >
TIR Prism
DMD Panel
TIR Prism
DMD Panel
2. DLP Projector –
Optical elements
(5) Projection Lens
It transmit Active Area of DMD on Screen
Fixed Focus Lens – Cannot control the zoom in Fixed distance
Variable Focus Lens (Zoom Lens) – Can control the screen size with zoom in Fixed distance
Used in DLP Engine with TRI Prism
DMD
Screen
< Converging Type Zoom Lens >
Screen
Telecentric Type Zoom Lens>
DMD
<
Used DLP Engine with Non-TIR Prism
3. How it works? –
FSC
Color Filtering by Rotating of Color Wheel
Color Wheel에 광이 입사하는 경우에는 일정한 형태의 크기를 가지고 있기 때문에 그 부분에
아래 그림과 같이 Color Filter들의 경계부위가 위치하는 경우 혼합 색이 되어 사용할 수 없다.
(단 DLP에서 White Peaking Mode=0인 경우) 그러므로 순색을 표현할 수 있는 시간이 길면
길 수록 Gray Ramp의 표현이 부드러워지고 순색의 밝기 또한 증가한다.
time for one field
Pure G time
Pure W time
Mixed Color time
Pure R time
Mixed Color time
Pure B time
Mixed Color time
Mixed Color time
3. How it works? –
FSC
Operation
※FSC=Field Sequential Color
Lighting on DMD in timely sequence
In case of transmitting Red Filter, Green and Blue is reflected and is useless
Blue and Green
light turned into
heat
Color Wheel
Red light
transmitted
33% efficiency
3. How it works? –
FSC
Brief Brightness Estimation
1) RGB Segment ( W=1, R:G:B Intensity= 1/3, R:G:B segment size= 1:1:1)
R = 1/3
G = B = 1/3
RGB size = 1/3 : Wo = R/3 + G/3 + B/3 = 0.333
2) RGB Segment ( W=1, R:G:B Intensity= 1/3, R:G:B:W segment size= 1:1:1:1)
R = 1/3
G = B = 1/3
W=1
RGB size = 1/4 Wo = R/4 + G/4 + B/4 + W/4 =
0.500
3. How it works? –
SCR
Operation
※SCR= Sequential Color Recapture
Scroll Lighting Whole RGB on DMD in timely sequence
Integrating
RGB색이
반사된
RGB
Filter에
CMY색은
투과하고
Rod의
Rod에
의해
Integrating
CMY색은
출사측에
입사된
CMY색은
백색광은
해당
Color
Rod의
반사되어
RGB색을
Filter가
입사측의
RGB
Integrating
Segment
위치하며,
투과되고
Mirror면에
Filter에
나머지
출사면의
의해
입사측으로
의해
RGB색은
다시
Size안에
해당
RGB
되돌아간다.
다시
RGB색은
RGB
Filter에
반사된다.
Segment를
투과된다.
입사하게모두
된다.
포함한다
Reflected
RGB
is re-reflected
by Integrating
Rod
INRod의
and
transmitted
by
RGB
Filter
3. How it works? –
SCR
Brief Brightness Estimation
Integrating Rod : Total size vs Hole Size ratio = 0.5
Total size Input vs Hole Input Intensity Ratio = 0.85
1) RGB Segment ( Wi=1, R:G:B Intensity= 1/3, R:G:B segment size= 1:1:1)
R = first transmission R(0.85*1/3) + G,B reflected MY of re-reflected R(0.85*0.5*2/3*1/3*2)
= 0.472
G,B is same as above G=B= 0.472
RGB size = 1/3 Wo = R/3 + G/3 + B/3 =
0.472
2) RGB Segment ( W=1, R:G:B Intensity= 1/3, R:G:B:W segment size= 1:1:1:1)
R = first transmission R(0.85*1/3) + G,B reflected MY of re-reflected R(0.85*0.5*2/4*1/3*2)
= 0.425
G,B is same as above G = B = 0.425
W=1
RGB size = 1/4 Wo = R/4 + G/4 + B/4 + W/4 =
0.569