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fMRI
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DLP Projector
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DLP- An Advanced projection
display technique
The DLP (Digital Light Processing) system is a revolutionary
technique on projection display, in which the signals are
digitally processed and translated into optical signals for
projection. The key part of DLP is DMD (Digital
Micromirror Device), developed by the Texas Instrument (TI)
Company, in which a rotational device with adjustable
reflection plane is mounted on a standard CMOS chip. This
technique not only challenges the currently popular LCD （Liquid
Crystal Display）techniques,
but also provides the possibility for further digitalized
information display on the basis of recording, receiving and
storing digital information.
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The DMD device
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The DLP technique features in
the signal digitalization. First, with digitalized
signals, the color gradation can be improved, image noise
lowered, image quality stabilized, and resolution increased.
Second, the use of DMD greatly improves the total optical
efficiency of the imaging device, leading to excellent image
contrast, brightness and uniformity. Therefore, the DLP
projector can provide high resolution, uniform image quality,
very sharp colors and high brightness. It’s also easy
to use and tune.
The DLP work flow is as
follows: the input signal is translated into RGB data, and
sequentially written into the SRAM of the DMD; and a bean of
white light is focused on the colored wheel, and the light
through the wheel is projected on DMD. When the wheel is
rotating, the Red, Green and Blue lights are sequentially
projected on DMD. Then if the red signal is needed for a
pixel, the micromirror on DMD correspondent to that pixel will
be set to ‘on’ and rotated to reflect the red light to the
right direction. It works the same for the Green and Blue
signals. The human eye takes in all the RGB signals and
processes them as true color. The image projected on the
surface of DMD can then be projected to a screen with
projection lenses.
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Advantages of the DLP
projection system:
1. Low noise level. Because of the digital nature of
DLP can virtually eliminate signal noise, the DLP is
very suitable for the basic structure of digital video
as a platform for developing digital video
communication.
2. Precise gradation. The digitalization results in
fine image quality with precise digital gradation and
color reproduction. DLP is superior to LCD with its
DMD reflection device which does not rely on polarized
light. And because each frame of image is presented
digitalized with 8-bit or 10-bit gradation, the same
digital image can be represented with the same quality
every time.
3. Reflection method. DMD is a reflection device with
more than 60% optical efficiency, which is a result of
total combination of reflection rate, filling factor,
diffraction rate and the effective ‘On’ period of
the mirror.
4. Seamless image reproduction. Each reflection mirror
on the DMD is a square mirror with an area of 16um2,
and a spacing of 1um, thus a more than 90% filling
factor. In another word, 90% of the incoming lights
can be effectively reflected to form a projection. The
whole mirror matrix is made uniform in size and
spacing, and independent of resolution. Higher DMD
filling factor provides higher image resolution, and
with the line-scan technique, more natural images can
be produced than with ordinary projectors.
5. High stability. The DMD device is fully tested to
meet all the semiconductor qualification standards, as
well as to tests of extreme operation conditions such
as thermal shock, temperature cycling, humidity
resistance, mechanical shock, vibration and
acceleration. The DMD and DLP present very high
intrinsic stability in the testing.
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Aspect
Ratio:
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4:3
(standard); 16:9 video, data
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Brightness:
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1400
max ANSI lumens
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Contrast
Ratio:
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1100:1,
full on/full off
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Data
Compatibility:
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VGA
through SXGA, 1152, Macintosh®
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Display:
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DLP
by
Texas
Instruments:
0.7”
XGA DMD DDR
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Light
Source:
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120-Watt
UHP(Ultra-High Performance), 3000 hours
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Native
Resolution:
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XGA
(1024x768)
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Projection
Lens:
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Zoom
Lens with manual focus and manual zoom adjust
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Projection
Methods:
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Front\Rear
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Video
Compatibility:
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NTSC
3.58, NTSC 4.43, PAL (all), SECAM (all), SDTV
(480i), EDTV (480p), HDTV (480p, 576i, 1080i)
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