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Duo 270c/ 280c discovery

I discovered today (much to my surprise) that the PB 270c/ 280c can be read without backlighting - albeit only in a sunlit area. It is not altogether easy to read the screen in this way, but it is not impossibly difficult, either. I have read that this was also true of the greyscale PB170/ 180, but did not know that it was possible on an early colour active matrix screen.

I do not have a 170 or 180. Are the active matrix greyscale screens about the same or better than the colour screens as far as being legible without backlighting is concerned?

 
Active Matrix grayscale screens are, if anything, MORE readable by passive light. There is only one set of liquid crystals for the light to passthrough to hit the backlight's reflection layer.

The original Macintosh Portable had an active matrix LCD, and no backlight. It was later revised to add a backlight. Many early PC laptops likewise had no backlight.

That said, LCDs that are designed to be passive-light only tend to have a different backing layer that makes them more suited for that use. Heck, even my MacBook Pro (non-glossy screen,) is usable, if only barely, by reflected sunlight.

 
Old news, I've used my 1400 in greyscale mode with the backlighting most of the way off plenty of times - for word processing and the like, its just the way to go. :)

 
that is true with every single LCD panel that has ever existed. ever.

the panel itself is in front of the light source, so simply because the light-source fails does not meant the panel is bad. LCD panels can far out-live their backlights.

my 3400c has the same problem, but unfortunately its screen is only visible with very bright lighting :-/

 
that is true with every single LCD panel that has ever existed. ever.
the panel itself is in front of the light source, so simply because the light-source fails does not meant the panel is bad. LCD panels can far out-live their backlights.

my 3400c has the same problem, but unfortunately its screen is only visible with very bright lighting :-/
Yes, indeed, I know all that. My question (in this particular instance, at least) was not uninformed.

There are those who rave about the fact that a PB180 can be used comfortably without backlighting, more or less like, say, a PB160, but without the ghosting, and other limitations of the passive matrix screens. I was merely making a similar observation about the active matrix 270c and 280c (which work VERY much better in this respect than the TFT 540c, 2300c, later active-matrix Wallstreets, or indeed a PB G4 - which is what I have to compare), and asking if anyone could comment on the merits of the FIRST active matrix colour screens used on powerbooks over against active matrix greyscale screens.

These were "glassy" screens, which seemingly used a different technology to what eventually came to be used in the "matt" screens that came later on. One of the advantages of the former, in my estimate, was their high level of readibility in a sunlit area. There were also noticeably sharper than the later TFT screens ever were, and looked more like the gem-like screen on a compact Mac than what we associate with TFT technology.

My question was answered reasonably well by another poster, though the final judgment would presumably require sitting in the sun with several of these machines lined up for comparison.

 
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