Display: Difference between revisions
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*a fixed hue (R, G, or B), |
*a fixed hue (R, G, or B), |
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*a value which can be set ''(still 18 bit (6,6,4), or now 24 bit (8,8,8))??'' |
*a value which can be set ''(still 18 bit (6,6,4), or now 24 bit (8,8,8))??'' |
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*and a chroma which depends on the relative strength of the room light and backlight. |
*and a chroma[http://en.wikipedia.org/wiki/Munsell_color_system] which depends on the relative strength of the room light and backlight. |
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Consider a single one of those 1200x900 pixels. A red one. If its value is 0, black, then lighting doesn't matter. If its value is 255 (or whatever, fully transparent), then in bright sunlight you see only white, and in a dark room you see fully saturated red. If its value is in between, in bright sunlight you see a gray, and in a dark room you see a |
Consider a single one of those 1200x900 pixels. A red one. If its value is 0, black, then lighting doesn't matter. If its value is 255 (or whatever, fully transparent), then in bright sunlight you see only white, and in a dark room you see fully saturated red. If its value is in between, in bright sunlight you see a gray, and in a dark room you see a grayed (ie desaturated) red. |
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Revision as of 20:54, 20 June 2007
See Hardware specification#Display.
Understanding the screen
The screen is composed of several layers. Starting at the back, there is a white LED backlight, a 1200x900 grid of color filters, a semi-reflective layer, and a 1200x900 LCD.
The brightness of the backlight can be adjusted. It has (how many?) settings, including off. (include an image of the backlight control)
The semi-reflective layer both reflects room light, and lets the backlight's light out. How much you see of each, depends on the relative strength of the two light sources.
- In direct sun, you see only reflected light. The backlight setting doesn't matter.
- In a completely dark room, there is no reflected light. So you only see the backlight, and if you turn it off, you see nothing.
- In between, you see some mix. You see more backlight if you turn down the room lighting, or you raise the backlight setting. You see less backlight when the room gets brighter, or you lower the backlight setting.
All color is created by the backlight and filters.
There are 1200x900 pixels. Each one has a single colored filter behind it. So each pixel is capable of either R, G, or B. Only one. It relies on its neighbors to provide the others. So each pixel has:
- a fixed hue (R, G, or B),
- a value which can be set (still 18 bit (6,6,4), or now 24 bit (8,8,8))??
- and a chroma[1] which depends on the relative strength of the room light and backlight.
Consider a single one of those 1200x900 pixels. A red one. If its value is 0, black, then lighting doesn't matter. If its value is 255 (or whatever, fully transparent), then in bright sunlight you see only white, and in a dark room you see fully saturated red. If its value is in between, in bright sunlight you see a gray, and in a dark room you see a grayed (ie desaturated) red.