Light output is 200 cd/m² at maximum. In order to achieve the operational requirement of Deep Dimming for night use on ships’ bridges, KME designed its own backlight inverter. This enables the display brightness to be dimmed by a rotary control on the front plate down to less than 1 cd/m². This 200:1 dimming ratio compares with a normal TFT monitor dimming range of 2:1 at best. The mains LED indicator on the front also has to be dimmed, as it would be too bright at night. KME’s design team introduced a special photodiode circuit to dim the LED automatically as the ambient light reduced.
Apart from exceptional EMC and EMI performance being required – so that there is no possibility of interference with other navigational or communications systems – the EN60945 standard also dictates that the monitor shall not be able to be switched off accidentally. Again a special circuit had to be designed to delay power down until after the on/off switch had been depressed for more than 3 seconds.
The Environmental conditions to which the monitor was subjected were severe. Extremes of temperature and humidity were taken into account and the monitor is certified for operation at minus 15º Celsius.
Screen resolutions up to SXGA (1280 x 1024 pixels) can be displayed with superb image quality. A multi-layer coated toughened glass panel gives contrast enhancement as well as protection to the TFT panel itself. The MP version will also display PAL/NTSC signals. Options exist for touch screen versions, and Slow Scan (15-30kHz) models for replacement of legacy monitors in older systems.
In addition to VESA standard fixings at the rear, there are also fixings for a basic metal stand or mounting bracket. The standard model operates from 90-265Vac. There is an optional 24Vdc version in process.
Copies of the EN60945 Report are available on request.
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