In September 1992, almost seven years ago, Videotronic presented the first ever colour/mono multispectral CCD camera to the world market. At the time people had either been using mono or colour cameras for surveillance purposes, mono cameras whenever sensitivity and IR compatibility was important, colour cameras whenever the colour as additional information was important. Colour cameras, however, were less sensitive and only suitable for a spectral response between 380 and 660 nm. IR sensitivity was not given due to the integrated IR cut-off filter typically placed in front of the CCD chip.
Successful engineering in the Videotronic laboratories resulted in the first CCD camera which was sensitive over the entire spectrum of the CCD chip, and the first TRI-Q camera was born.
What is TRI-Q? TRI stands for three, and Q stands for quality. As a result the camera comprises three quality features in one, namely:
p Colour pictures during the day.
p Mono pictures in low light conditions.
p Mono pictures with additional IR lamps in total darkness.
Next generation TRI-Q day/night cameras
Videotronic's goal for the next generation TRI-Qs was not an easy one. These cameras had to:
p Improve sensitivity by a factor of two.
p Produce true colour pictures (>90% compared to a conventional colour camera).
To improve the sensitivity of the camera Videotronic had to develop a new CCD chip, the end result of which is that the new 'near infrared' CCD chip inside the TRI-Q camera has improved sensitivity by a factor of four compared to the older models.
The next generation TRI-Q, also uses a so-called overlay low pass filter (OLPF) in front of the CCD chip which is sensitive over the entire spectrum of the CCD chip with a kink (cut) between 680 and 780 nm. As a result the camera delivers excellent and true colour pictures (almost 95% compared to conventional colour cameras). Due to an extremely high sensitivity of the CCD chip the camera will only switch to mono in real low light conditions, ie 0,34 lux. Above this lux level the camera continues to deliver colour pictures with very low noise.
When using additional IR lamps at night, the camera plays the real trump. Due to the high sensitivity of the CCD chip and the spectral response from 780 to 1100 nm at almost 100% relative sensitivity, the camera delivers crystal clear high resolution monochrome pictures. Since the relative sensitivity of the CCD chip in the infrared spectrum is very high (near infrared), one can even use IR lamps between 730 (cherry red) and 800 nm (dark red) for short to medium distance applications.
The key advantages of the new TRI-Q camera series are:
p High resolution 570 TV lines (monochrome), 752 (H) x 582 (H) pixels.
p Very high sensitivity to light, only 0,015 lux at the faceplate.
p New 'Near infrared' HQ interline transfer CCD chip (SONY).
p Excellent colour reproduction (no weakness on the red/green spectrum).
p Superb IR performance (10 times more sensitive than previous models).
p Automatic switch over from colour to mono under low light conditions.
p Adjustment of camera parameter via push-buttons at the rear panel.
p Optional remote configuration/control via RS232/RS485.
p 12 V d.c. or 230 V a.c. version with linelock synchronisation.
p High speed auto shutter up to 1/100,000th sec.
p Extremely low smear (reduced by further -10 dB).
p Attractive price.
p Also available as 'System Camera' version.
For details contact LS Technology on tel: (012) 664 6186, or fax: (012) 664 6184.
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