The point about the Epson display is that it has much higher resolution than usual. Most EVFs have just 0.23 megapixels and look pretty grainy, but this one has 1.44 megapixels and should look much sharper and smoother, helped by an 'analog driver' which produces smoother colour gradations.
This new technology could be highly significant for two types of camera: superzooms and hybrid D-SLR replacements.
Digital compact cameras with long-range zoom lenses, like this Nikon P90, cannot be fitted with optical viewfinders because they do not have an SLR viewing system, and the zooming range is too great for a separate, linked viewfinder. Instead, you get a second, smaller LCD display which you see through the viewfinder eyepiece. This is basically another, smaller LCD, just like the one on the back. Usually, the resolution is too low for accurate focussing or examining fine detail.
The other application for high-resolution EVFs is in hybrid D-SLR replacements like the Panasonic Lumix G1, above. Although it looks like an SLR, the G1 has no mirror. Here, you can see straight through to the sensor itself. During normal viewing, the image is formed on the sensor and transferred either to the LCD on the back or to the electronic viewfinder.
EVFs allow cameras to be smaller, more sophisticated and yet mechanically simpler. There are some serious drawbacks to EVFs, though, which affect the relative strengths of hybrid cameras versus D-SLRs:
• Even the latest high-resolution EVFs lack the visual clarity of an SLR's optical viewfinder
• EVFs consume much more power than optical viewfinders, which usually have a few status LCDs
• Conventional optical viewfinders get their illumination from the subject itself, so their brightness always matches the conditions. EVFs, however, can get swamped in very bright light or prove overpowering in dimmer conditions, even with automatic brightness adjustments
