JVC DLA-G20 Sales Manual page 21

Operating precautions
8 In dark areas
The screen may become slightly The border of the screen may
brighter than the surrounding dark become slightly brighter than the
area, even though the projector is surrounding dark area.
not projecting images (when muting (When projecting a window, etc.).
or not receiving signals).
The brighter areas will not stand out while the projector is projecting images.
9 The projector's surroundings
The D-ILA multimedia projector generates heat, so adjust the
temperature in the room with ventilation or air-conditioning,
referring to the table below for the energy generated by each type
of projector. For optimum cooling efficiency and maintenance,
refer to "Installation" on pages 34 to 35.
When the projector is transferred from a cold to warm place,
or the room temperature drastically increases, it may cause
condensation to form that will negatively affect the projector. To
avoid or remove condensation, wait for more than an hour, then
turn the projector on. In
DLA-G20 / DLA-S15
addition, avoid humid environ-
2260 kJ/h
Heating value
540 kcal/h
ments, as it will also cause
condensation to form. (Keep
the humidity as low as possible.)
10 Do not block the ventilation
openings.
Do not cover the projector with a cloth during operation in order to
avoid increasing the temperature in the projector, and do not place
the projector near other equipment. It may disturb the flow of air
and cause an increase in temperature. Small spaces may also
hinder maintenance. Before you place the projector, refer to
"Installation" on page 34 to 35.
11 The light source lamp must be
replaced periodically.
It is recommended to replace the lamp periodically to maintain a
clear picture. The lamp is mounted in a detachable housing for
easy replacement. For more information, consult your JVC dealer.
• Life of the light source lamp: about 1,000 hours
• Model No.: DLA-G10-LAMP
• Please note that lamp life is a guideline only, and is not a
guarantee.
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12 When should the lamp be
replaced?
The light source lamp in the D-ILA multimedia projector will
gradually become exhausted as it is used, with the brightness
lessening over time. The lamp should be replaced when its
brightness becomes about half that of a new lamp.
Do not turn the projector on and off frequently. It will
exhaust the lamp faster and shorten its life.
13 Lamp expiration warning
An orange "LAMP" indicator lights when the lamp is within 100
hours of expiring, so you know when it is time to replace it. An
indication is also displayed on the screen for a few seconds after
the projector is turned on. The orange indicator starts blinking
when the expiration date gets closer. The projector has a timer
with which you can confirm the number of hours the lamp has
been used.
14 No forced shutdown when the
lamp reaches its expiration date during
projection.
It can be considered a selling point for our product, as many of
the other companies' projectors automatically shut down when the
lamp's expiration date is reached. Once the projector is turned
off, however, it cannot be turned on again, so do not turn the
projector off during an important meeting. To avoid any problems,
keep a spare lamp handy as soon as the orange indicator lights.
(You can cope with sudden lamp requirements by keeping spare
lamps on a shelf.)
If the lamp does not light, replace the lamp after the
projector is turned off and the plug is pulled out. Before replacing
the lamp, wait for a while until it has cooled down, in order to
avoid any injuries caused by touching the hot lamp just after
turning it off. For more details about lamp replacement, refer to
the instruction manuals of the projector and spare lamp.
15 The lamp automatically turns off
after a certain period of time passes
without any sync signals.
If the projector does not detect any incoming sync signals for a
specified period of time, the sleep function automatically turns it
off. This function avoids unnecessary lamp exhaustion and also
saves electricity, even in situations where you may have forgotten
to turn the projector off.
You can easily set the amount of time from the remote controller.
16 Changing the aspect ratio
The D-ILA multimedia projector can handle aspect ratios of 5:4,
4:3, and 16:9. Each projection method is shown below. Aspect
ratio is switched automatically according to the type of input
source. For NTSC and HDTV, 4:3 and 16:9 can be switched
manually to assure compatibility with the DVD squeeze mode and
4:3 HDTV presenter camera.
5:4 projection
4 4
5
3 4 3
By contracting the left and right sides,
4:3 is standard.
5:4 can be obtained (e.g.: S-XGA).
16:9 projection
4
4
16
3 9 3
By contracting the top and bottom sides,
4:3 is standard.
16:9 can be obtained (e.g.: HDTV).
16 16
4
9 3 9
It is not possible to obtain a 4:3 picture
For the 16:9 screen by contracting the left and right sides.
17 Picture estimation
on a large screen
With 4:3, view the
picture at a distance
of 2.55 times the Screen
screen height.
With 16:9, view the
picture at a distance
of 3.4 times the
screen height.
To estimate a picture projected on the screen, the picture is
usually viewed near the screen.If the picture is viewed at a
distance of 40 to 50 cm from a 180-inch screen, the picture
quality is the same as when viewing an 18-inch CRT monitor at a
distance of 4 to 5 cm. That is, the picture on the 18-inch monitor
is viewed with a 10x loupe. This is not a correct estimation
method.
Suppose that a person with standard eyesight of 1.0 is
estimating 1000 vertical dots with resolution of 1000 TV lines. As
the vertical length of the 180-inch (4:3) screen is 2.74 m
(2,740 mm), the length of one dot is 2.74 mm. The maximum
distance with which this person can dissolve 2.74 mm is about
D-ILA Method Present Condition and Subject Operating precautions
9.42 m. Actually, unless the distance is 70% of maximum
distance (about 7 m), this person cannot judge one dot with ease.
Thus, the proper viewing distance is about 7 meters. Estimate
the picture at this distance. This distance is about 2.55 times the
vertical length of the screen. Therefore, if the screen size is
different, use the value as a guide obtained by multiplying the
screen vertical length by 2.55. For 16:9 aspect ratio, multiply the
screen vertical length by 3.4.
• The dots that you see near the screen are the D-ILA device's
pixels and not abnormalities.
18 Fan noise
The D-ILA multimedia projector uses a high-output xenon lamp
and generates heat. Because a fan is used to keep the projector
cool, fan noise is produced. To attenuate this noise, various
measures are taken as shown below. However, when muting or
absorbing the noise, take care not to prevent heat dissipation.
• Model: 46dB
DLA-G20 /DLA-S15
1m
• Level (Distance of 1 m,
A weighting, average): 1m 1m
49dB 44dB
46dB
1m
45dB Ceiling : 45dB
19 Fan performance
Several fans are installed to cool the D-ILA multimedia projector.
These fans have a total capacity of 303.6 m3/h (5.06 m3/min.)
(DLA-G20/DLA-S15).
20 Burning
As with TVs and other display, burning occurs when a high
contrast still picture is projected continuously.
• The D-ILA device incorporated in the D-ILA multimedia projector
may cause burning.
• Once burning occurs, replace the part.
• When a 16:9 picture with the top and bottom sections cut is
projected on a 4:3 screen for a long time and the picture source is
switched to 4:3, the boundary line of the 16:9 screen (burning)
may appear.
21 Control from the switcher
The D-ILA multimedia projector can be controlled from a switcher,
controller or personal computer via the RS-232C interface. For
"RS-232C control specifications", consult your JVC dealer.
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