Part 1: General Information
1-7
4. COMMENTARY
4.1 Optical System
High brightness and high contrast are implemented at a low cost by a newly designed
×
1.4 wide zoom lens and an improved LCD panel, combined with the Canon's unique 3P
prisms.
●
×
1.4 wide zoom lens
A wide zoom lens with a short focal length of 20.3 mm and high magnification of
×
1.4
is designed as a bright large-aperture projection lens (F1.6).
The optical system has 10 groups of 10 lenses, including 5 groups of zoom lenses.
The number of lenses has been reduced and the zoom lenses have been designed
optimally using a replica aspherical lens for G1 and double-sided aspherical lens for
G9 to suppress distortion aberrations due to widened angles.
All lenses are made from lead-free glass.
●
LCD panel
The new type of LCD panel has a higher open area ratio than conventional ones by
improving production technologies to increase efficiency of using light.
* Since the wide projection lenses are used, the F value increases, but the light
intensity is the level of the previous model.
●
3P prism
Like the clear prisms for X1/S1, the 3P prism produces images with uniform color on
the screen.
The cost has been cut down by reducing the number of parts.
●
Projection screen size
A29 to 200" screen display at the proper projection distance of 1.1 to 8.0 m
(See 6.1 Relationship between screen distance and screen size.)
4.2 Functions
●
Zoom/focus
The Wide/Tele zoom ratio is 1.4, and the projection size can be changed by manual
zooming within the range.
The focus can be adjusted to the correct point manually.
●
Monochrome expansion
It is effective when projecting dark images at night scenes or blurred images with a
low contrast.
When this function is turned on, the video signal output is controlled automatically to
maximize the black and white levels of output images.
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