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POS-displays
See Galleria below.
To install video in shop-windows require some hints and tips:
Screen brightness has a fixed relationship to image area. A screen of 2m
squared is 50% dimmer than of one of 1m squared.
Screen area increases drastically relative to its diagonal size. A small
increase in the diagonal size is a big increase in image area. A 100” screen has
four times the image of a 50” screen – and thus only 25% its brightness.
Screen brightness is also relative to gain. But beware of some very creative
claims here. The measuring of gain for a certain screen is not always what the manufacture claims it is. Yet another reason you should TRY BEFORE BUY! And make your trial in a truly representative location – rather than a conveniently controlled showroom or office.
Be very careful about vertical viewing angle: it’s a major cause of unexpected disappointment. The line of peak brightness is a line you draw from the projector lens, running through the centre of the screen. This is a law of physics - unless screens have specific optical technologies (such as diffusion-screens).
Our eyes don’t register light on a normal scale. We can only register a
difference when light levels double or halve. This is why the apparently superbrightscreen in the showroom can look so weak in a shop window – and why a projector of 2,000 ANSI lumens seems hardly brighter than one of 1,000 ANSI lumens.
Contrast is the key. The word ‘bright’ itself is misleading when applied to
projection. Yes you do need a threshold level of brightness. But without proper
black levels the image is a wash-out. Front screens – unlike rearpro screens –
cannot distinguish between projected and other light; so ambient light ‘pollutes’
the black – ruining the contrast.
Without contrast there’s no image, no matter how ‘bright’ the image is.
Optical screens is the only screens that can effectively combat high
levels of ambient light and enhance projector contrast.
Screens in shop windows present special problems. Glass is reflective. The
greater the angle the light strikes glass, the more reflective it becomes; after
approximately 45° it’s more like a mirror. A normal office has approx 500 lux
ambient light; outside on a bright sunny day it can be >120,000 lux (i.e. over 240 times brighter). So in some locations the brightest of projector/screen
combinations might not be viewable at certain times of the day (unless the glass is treated). It needs planning and a sense of reality; each installation is different. This is why we have many types of screen materials and we always encourage customers to try before buy.
Small demonstration of a "video-tube" by click HERE.
POS-displays
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