dlp projector

DLP PROJECTOR

FDD@H

1. What is DMD?

2. DLP projector

- Why should we choice DLP projector?

- Optical configurations

- Optical elements

3. How it works?

- FSC

- SCR

Agenda

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

1. What is DMD ?

2. DLP Projector – Why should we choice DLP projector?Why should we choice DLP projector?

Image Quality - PixelizationPixelization (fill factor)

DLP= ‘Seamless’, Filmlike

LCD= Grainy, Pixellated

- Contrast RatioContrast Ratio

DLP= simple optics: easier light management

LCD= complex optics: more difficult light management

- SharpnessSharpness (color alignment)

DLP= no misalignment

LCD= misalignment likely over time

- Video QualityVideo Quality

DLP= fast switching: minimal ‘lag’ (few μs)

LCD= slow switching: significant ‘lag’ (tens of ms) smearing for fast moving video

DLP™ = large ‘active’ area LCD = smaller ‘active’ area

DLP™ LCD


- Color QualityColor 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

- Smallest & Brightest DLP= simple optical system,

good reflectivity

LCD= complex optical system

wavelength

LCD

wavelength

DLPTM

DLPTM LCD


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

Number of DMD

2. DLP Projector – Optical configurationsOptical configurations

1 Chip DLP 3 Chip DLP

2. DLP Projector – Optical ConfigurationsOptical Configurations

TIR prism

Non TIR Prism DLP TIR Prism DLP

Reflector (Elliptical Surface)

Lamp

Front Glass (UV Cut Coating)

Mirror

Color Drum (R,G,B,W segment)

※Color Wheel

Condenser Lens C3 (Aspherical Surface)

DMD Panel

Projection Lens

TIR Prism (Total Internal Reflection)

Condenser Lens C2

Condenser Lens C1

Aperture

Integrating Rod

2. DLP Projector – Optical elementsOptical 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) 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

0

10

20

30

40

50

60

70

80

90

100

380 400 420 440 460 480 500 520 540 560 580 600 620 640 660 680 700 720 740 760 780

Wavelength(nm)

Tra

nsm

ittan

ce(%

)

AOI=0 deg

AOI=10 deg

Material: Borofloat + UV Coating


Reflected UV light

(3) Rod Integrator

- through internal reflects, it makes uninformative incident light distribution “rectangular uninformative light”

Type: Solid Rod – Glass or Plastic

Light Tunnel – Mirror

Light Distribution Light Distribution from the inputfrom the input

Light Distribution Light Distribution from the outputfrom the output

Avd: good transmission. Strong against heat DisAvd: easy to broken, easy to get dust , long

Avd: easy to install, dust free, ShortDisAvd: less transmission, weak for heat

in out


(3) Color Drum & Wheel

Optical instrument filtering color by Color Filter assembled with Motor \

< Color Drum >

< Color Wheel > < SCR Color Drum >


(4) Illumination Lenses

It guides lights from Rod Integrator into valid dimensions of DMD

f1 f1

f2 f2

h

h’

θ θ’

t

L1

L2

L1

L2

R1 R4

R5 R6

R2 R3

(m)= h’ / h

= f2 / f1

(t)= 2*(f1+f2)

< JT30 >

f1 = 9.53, f2 = 22.79

※ m = 2.39 배


(5) Mirror

It changes light path or controls light position on DMD


(5) (TIR Prism)

Using air gaps between two prism, it makes selective reflect of transmission

<in : reflect, out : transmission>

in

outin

out

<in : transmission, out : Reflect >

air gapair gap

DMD Panel

TIR Prism

TIR Prism DMD Panel


(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

< Telecentric Type Zoom Lens> < Converging Type Zoom Lens >

Used in DLP Engine with TRI Prism Used DLP Engine with Non-TIR Prism

DM

D

Scr

een

DM

D

Scr

een


3. How it works? – FSCFSC

Color Filtering by Rotating of Color Wheel

Color Wheel 에 광이 입사하는 경우에는 일정한 형태의 크기를 가지고 있기 때문에 그 부분에 아래 그림과 같이 Color Filter 들의 경계부위가 위치하는 경우 혼합 색이 되어 사용할 수 없다 . ( 단 DLP 에서 White Peaking Mode=0 인 경우 ) 그러므로 순색을 표현할 수 있는 시간이 길면 길 수록 Gray Ramp 의 표현이 부드러워지고 순색의 밝기 또한 증가한다 .

time for one field

Pure G time Pure W time Pure R time Pure B time

Mixed Color time

Mixed Color time

Mixed Color time Mixed Color

time


Operation

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

※FSC=Field Sequential Color

Lighting on DMD in timely sequence


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? – SCRSCR

Operation

Integrating Rod 의 출사측에 Color Filter 가 위치하며 , 출사면의 Size 안에 RGB Segment 를 모두 포함한다Integrating Rod 에 입사된 백색광은 RGB Segment Filter 에 의해 해당 RGB 색은 투과된다 .RGB 색이 투과하고 CMY 색은 반사되어 Integrating Rod 의 입사측으로 되돌아간다 .반사된 CMY 색은 Integrating Rod 의 입사측의 Mirror 면에 의해 다시 RGB Filter 에 입사하게 된다 .RGB Filter 에 의해 CMY 색은 해당 RGB 색을 투과되고 나머지 RGB 색은 다시 반사된다 .

※SCR= Sequential Color Recapture

Scroll Lighting Whole RGB on DMD in timely sequence

Reflected RGB is re-reflected by Integrating Rod IN and transmitted by RGB Filter

3. How it works? – SCRSCR

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

dlp projector

Documents

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