Canon D78-5252, Руководство по обслуживанию

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Part 1: General Information
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High-refractivity 4P color synthesis prism
The lines at the center of the screen and bad images, which are problems with the
conventional cross-dichroic prism, are eliminated by using a configuration in which
the dichroic membrane is not crossed in the prism. Since the panel and B panel are
not faced with each other, light does not leak to other channels, and color shading can
be suppressed to ensure high-quality video output.
By using a high-refractivity glass, the back focus can be suppressed during air
conversion of the projection lens, so a small lens can be designed. By dividing the
prism between dichroic membranes into two parts, shading of the effective light flux
on the exit side is suppressed and the prism is made compact.
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Large aperture zoom lens: F1.6
A large aperture F1.6 projection lens suitable for the LCD panel with a microlens has
been optimally designed. The zoom has been designed so that four of six groups are
moved to minimize aberrations and achieve the highest brightness in its class, 1100
ANSI lumen. (The optical system has 11 groups of 12 elements.)
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Fluorite field lens
The fluorite with a high heat conductivity is used as a material of the field lens located
adjacent to the LCD panel. A deflector is attached to the flat part of the fluorite field
lens. This reduces thermal load on the deflector and reduces the number of parts.
As the LCD projectors are getting smaller and brighter recently, the heat in the
projector is becoming a problem. Especially, there is a problem that the deflector is
deteriorated by heat in a short time.
A general measure is to attach a deflector to a flat plate of sapphire with a heat
conductivity approx. 40 times as high as glass to dissipate heat, but using sapphire
costs high.
This product uses a convex fluorite with a thermal conductivity approx. 10 times as
high as glass and 6 times as thick as the sapphire plate to provide heat dissipation
equivalent to or higher than that of sapphire and high cost-effectiveness.
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Free curved surface mirror
A free curved surface mirror is used in the red light path optical system whose optical
path length is different from that of other channels.
The Canon's free curved surface design technique reduces the number of parts and
reduces weight drastically compared with the conventional relay optical systems.
The three-panel LCD projectors with three LCD panels decomposes light from the light
source into three color components R, G, and B, and passes them through separate
LCD panels. One of the three light paths from the light source to the LCD panels is
longer than the other two, and the relay optical system consists of three lenses and
two mirrors.
This product consists of two parts: "free curved surface mirror with two integrated
sides" and "concave mirror".
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Teletype illumination optical system
The teletype illumination optical system in which a concave lens and a convex lens
are laid out from the light source lamp is used to reduce the overall length of the
illumination optical system.