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Projection Lens 

(1111)
(1001)
(0100)
(0010)
(0001)
(0000)

(4-Bit Example)

Video Field 

TIme

(Sensation of Gray Scale 

by Viewer’s Eye)

(Note: For simplicity, only central col

µ

mn is addressed 

and no light source is shown.) 

G

R

B

1

2

3

4

5

6

7

When the mirror rotates, it reflects incident light either

into or out of the projection lens to create a burst of

digital light pulses, which the eye interprets as an analog

image.

In binary pulse width modulation, the DMD accepts

electrical words representing the gray level of bright-

ness at its input, and puts out optical words, which are

interpreted by the observer’s eye as analog brightness

level.

Taking 4-bit word as an example for simplicity, each bit

in the word represents a time duration for light to be ON

or OFF, and the time durations have relative value of

2°0, 2

1

1, 2

2

2 and 2

3

3 or 1, 2, 4 and 8 (

Figure 7.).

The video field time is divided into four time durations

of 1/15, 2/15, 4/15 and 8/15, and 24 or 16 equally spaced

gray levels (0, 1/15, 2/15, 4/15, …, 15/15) are produced

by all the combinations of bits in the 4-bit word.

Currently available DLP systems are of either 24-bit color

(8 bits or 256 gray levels per RGB) or 39-bit color (10

bits or 1024 gray levels per RGB).

In the DLP displays of pulse width modulation, “bit-

splitting technology” is combined to produce a “true-

analog” sensation with greater accuracy and stability

than can be achieved by analog projection systems.

1

The DC light source lamp flickers 180 times or 210

times per second

2

This color filter splits light into RGB primary colors.

The rotation-detecting sensor should be synchro-

nized with the timing to turn off the lamp at the seam

of color filter. The maximµm rotating speed is 7200

rpm.

3

This lens condenses the light split by the color filter

and projects it to the effective area of the reflection

mirror.

4

This mirror reflects the light projected to the effective

area of the DMD.

5

This

chip turns on and off in proportion to each

color element per dot depending on the input source.

6

This lens magnifies and projects the incident light

coming from the DMD.

7

Projected light (RGB components) is interpreted by

viewer’s eye as a synthesized color image due to

after-image phenomenon.

* On the main PWB, the color components are split

per dot depending on the input source, and the

information is sent to the DMD.

1. Turn on the power (make

sure the lamp lights up) and
warm up the unit for 15 min-
utes.

»

Make the following settings:
Press S5001 to call up the process mode and
execute S2 in the SSS menu. Now the system,
with the PC board not included, is initialized. Do
not execute S1 because otherwise the PC board
will be initialized.
To adjust the PC board, follow the instruction in
"Adjusting the PC Interface". (See page 30)

1. Feed the 100% blue-only

signal. Make the following
choice.
Group : A/D
Subject : B-D

»

Using the control switches or the remote controller
buttons, adjust the data so that the signal be-
comes bit-less (noise).

1. Feed the 100% green-only

signal. Make the following
choice.
Group : A/D
Subject : G-D

»

Using the control switches or the remote controller
buttons, adjust the data so that the signal be-
comes bit-less (noise).

1. Make the following choice.

Group : A/D
Subject : BRIGHT
Make sure the data value is
125.

2. Make the following choice.

Group : A/D
Subject : R-BRIGHT,

G-BRIGHT,
B-BRIGHT

Adjust until the data value
becomes 135 or so.

»

With the set's control switch or the remote-control
button, adjust the data until the black-side noise
becomes bitless.

1. Make the following choice.

Group : A/D
Subject : GAIN

2. Feed the 100% red-only sig-

nal. Make the following
choice.
Group : A/D
Subject : R-D

»

Using the control switches or the remote controller
buttons, adjust the data so that the signal be-
comes bit-less (noise).

1. Make the following choice.

Group : A/D
Subject : GAIN
Initial value :  137

»

With the set's control switch or the remote-control
button, adjust the data until the white-side noise
becomes bitless.

1. Feed the 32-step gray scale

signal (XGA 60Hz).
Group : A/D
Subject : R-BRIGHT

B-BRIGHT

»

Adjust the R-BRIGHT and B-BRIGHT data for the
balance on the gray scale.
(Adjust to the best point.)

1. Feed the green-only SMPTE

pattern signal.(XGA)
Group : A/D
Subject : GAIN

»

Adjust the G-GAIN data until the gradation of the
portion 

1

 (95% and 100% white) shown below

can be slightly recognized.  Make sure also that
the gradation of the portion 

2

 (0% and 5% black)

is visible.

1. Feed the NTSC mono-

scope pattern signal.

2. Group : VIDEO 2

Subject : N358-DLY

(10)

N443-DLY

(0)

PAL-DLY

(10)

SECAM-DLY (10)

Make sure the settings are

    as above.

3. Group : VIDEO 1

Subject : NTSC-H

»

Using the control switches or the remote controller
buttons, adjust the data to have the same
overscan.

1

2

1. Feed the split color bar sig-

nal.
Group : VIDEO 1
Subject : PICTURE

2. Connect the oscilloscope to

TP805.

»

Using the control switches or the remote controller
buttons, adjust the black-to-white (100%) level
difference to 2.1 ±0.02 Vp-p.

100% White

2.1Vp-p

1. Feed the split color bar sig-

nal.
Group : VIDEO 1
Subject : AGC

2. Connect the oscilloscope to

TP805.

»

Using the control switches or the remote controller
buttons, adjust the black-to-white (100%) level
difference to 1.65 ±0.02 Vp-p.

1. Feed the baseband (split

color bar) signal.
Group : VIDEO 1
Subject : BRIGHT

2. Press the control switch or

the remote control’s mute
button (to set the gamma
correction to the process
setting).

»

Using the control switches or the remote controller
buttons, adjust the setting until the black signal
becomes bit-less and set to -3 point of value.

1. Feed the split color bar sig-

nal.
Group : VIDEO 1
Subject : TINT

2. Connect the oscilloscope to

TP807.

»

Using the control switches or the remote controller
buttons, adjust the data to have the -(B-Y) wave-
form downhill straight.

1. Feed the split color bar sig-

nal.
Group : VIDEO 1
Subject : N-COLOR

2. Connect the oscilloscope to

TP804.

»

Using the control switches or the remote controller
buttons, adjust the difference between the 100%
white portion and the red portion to 0.0 ±0.02 Vp-p.

   (same as 100% white)

100% White Red

100% White

1.65Vp-p