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In addition to its extreme resolution and high contrast,
the SXRD device used in the SRX-R320 projector
has the following remarkable
technological features:
‘Normally Black Mode’ System
In every type of projection system, displaying absolute
black is a major issue – as this helps to achieve a high
contrast ratio. In other words, the contrast ratio of a projector
depends on how effectively the light from the source can be
blocked, so it does not leak through the display device.
All Liquid Crystal Display (LCD) devices control the amount
of light to be projected by applying an electric field to the
liquid crystal gap. In typical LCD devices, black is produced
when an electric field is applied across the liquid crystal
cell gap. However, molecules near the surface of the
glass substrate may not be accurately controlled due to
the influence of the alignment film. This is not an issue for
bright images but, when displaying dark images, light may
tend to leak from the LCD device, since the molecules near
the surface are less accurately controlled. This results in a
creamy black instead of a deep black.
The SXRD device does not exhibit these characteristics.
This is because the ‘normally black mode’ system displays
black when the electric field is not applied and, because all
molecules are in the correct alignment, the polarized light
alignment is also optimized. The direct result is a far deeper
black level, leading to a high contrast ratio.
Thin Liquid Crystal Cell Gap
Another important factor allowing for the high contrast of the
SRX-R320 is the SXRD device’s ultra-thin cell gap of less than
2 micrometers. With conventional ‘vertically aligned liquid
crystal’ systems, a thin cell gap could not be achieved. Sony
has overcome this difficulty through the use of innovative
planarization technology in the silicon backplane structure
and an advanced silicon wafer-based assembly process.
The SXRD device also adopts a structure that does not use
’spacers’. These are columns found in conventional reflective
liquid crystal devices to maintain a constant gap between
the liquid cell floor and the top of the device. Spacers tend
to both scatter and reflect light, which can impair high-
contrast pictures. In the spacer-less SXRD device, these
artifacts are no longer seen.
Short Response Time
The thin cell gap structure in SXRD devices also contributes
to an ultra-fast response time of 2.5 milliseconds (for both
rise and fall). The SXRD device reacts promptly to an
instantaneous change of picture content, enabling SXRD-
based projectors to display smooth motion. Consequently,
the SRX-R320 virtually eliminates motion blur; a particularly
significant benefit when presenting content that includes
fast-moving objects.
Thermal Management by Peltier Device
The SRX-R320 adopts an advanced thermal management
system that combines a Peltier device and a thermal
sensor. The Peltier device is placed at the back of the
SXRD device to cool or heat the panel by applying current.
The thermal sensor attached to the panel measures the
panel temperature and feeds back this data to the Peltier
device so that the temperature can be precisely controlled.
Thanks to this system, the SXRD device is maintained under
temperature conditions that optimize performance.
12-bit SXRD Driver
The SRX-R320 utilizes a 12-bit display panel driver for
reproducing extremely natural images.
High-Density Pixel Pitch 8.5 µm
Thin Cell Gap (2.0 µm) Spacer-less
Light
Inorganic
Alignment Layer
Liquid Crystal
Glass Substrate
Silicon Backplane
Narrow Inter-Pixel
Spacing (0.35 µm)
Aluminium Pad
• High fill factor
• High reflectivity
• High reliability
• Short response time < 2.5 ms (for both rise and fall)
• High Device Contrast ratio 4000 : 1
• 4 x Full-HDTV (4096 H x 2160 V pixels)
SXRD Cross-Section Diagram
SXRD Technologies
