Description; Optics - Canon LV-S3E/D78-5423 Service Manual

Part 1: General Information

6. DESCRIPTION

6.1 Optics

The optical system employs a compact zoom lens, 0.55-type (0.5-type, nominally)
liquid-crystal panels with microlenses, an internal optical system optimized for panel's
size and a 160-watt UHP lamp.
This optical system is the key behind this compact, micro-portable projector.
Disapproval to reproduce optical drawing
1.2× compact zoom lens
This 1.2× projection lens has a negative-positive-positive-positive-positive 5-group
zoom (with 3 groups mobile) based on a 9-group 9-element lens configuration.
The use of two both sided aspherical lenses (G2 and G8) from plastic mold has
decreased the front-bead diameter and number of lenses.
These features have resulted in a compact, wide-angle lens that produces high image
quality with minimal aberration and the like.
All of the materials used for the lenses are lead-free.
Screen size
This product can display images with excellent fidelity on 100-inch screens at a throw
distance of 3.2 meters.
Refer to the table below for the relationship between the throw distance and the screen
size.
Distance
Screen size
* The projector displays correctly at screen sizes between 34 and 200 inches; the quality of projections at other screen
sizes is not guaranteed.
Internal optical system
For the prism that engages in color composition, a low-volume cross prism is used to
make the optical box compact.
To counteract heat, sapphire bases are used for part of the boards that attaches the
polarizer.
Liquid crystal panels
This 0.55-inch liquid crystal panels are the transmissive type. With the same number
of pixels as in a real SVGA display, the aperture ratio is 48%; the addition of micro-
lenses increases the efficiency of light utilization.
Lighting system
A 160-watt UHP lamp with 1 mm arc length is used for the lighting system. This lamp
also has a longer service life than the conventional lamps.
The design of the pair of luminosity leveled elements (fly eye integrator) right after the
first emission of the lamp has been optimized, thus greatly improving the efficiency of
light utilization.
1 m 2 m 3 m
26.4 - 31.4 52.3 - 62.2 78.1 - 93.0
4 m 5 m 6 m
104 - 124 130 - 155 156 - 185
1-12
7 m 8 m
182 - 216 198 - 313