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In addition to its extreme resolution and high contrast,
the SXRD device used in the SRX-R320P 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-R320P 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-R320P virtually eliminates motion blur; a particularly
significant benefit when presenting content that includes
fast-moving objects.
Reliable Display Device
The SRX-R320P uses bright and highly powerful lamps. As
a result, special attention has been paid to the reliability
of the SXRD device. The inorganic materials utilized for
the alignment layer of the SXRD device are resistant to
deterioration or deformities that could occur due to the
intense heat and light generated by the powerful lamp
system.
12-bit SXRD Driver
The SRX-R320P 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