This goes into ancient, non-obvious info about how transistors work. Different types of transistors have different current characteristics (distinction between off/on/transition). A binary one can be represented by carrying current (on), showing a voltage (off), or a complementary pair of transistors (one off, one on). Some show different current consumption when off than when on, others (the complementary pair = CMOS, Complementary Metal Oxide Semiconductor) are identical off and on, but take current to switch between the states.
How does this relate to the question? An LCD (or similar) display is made up of an array of transistors. If the technology uses a CMOS-type switch to turn the pixels off and on, the current should be the same in either state (but very low). If the transistors in the display are not CMOS (I haven't checked recently how many variations there are in this part of the design), they will draw (probably very slightly) different amount of current in on and off states. In a transmission-type LCD, illumination is really the highest current drain. In contrast [pun!] in a CRT, brightness is the result of current flow from the electron gun to the phosphor layer, so a brighter pixel is definitely the result (or cause?) of higher current flow. How this compares to the current to heat the filament and to bias the tube is something to consider (both are quite high), but you can see (on a cheaper CRT) the scan pattern change when a brighter image is displayed, indicating higher current draw. --Don Ellis On Tue, Dec 23, 2008 at 9:43 AM, Scott Kokotovitch <[email protected]>wrote: > > Here's a silly question. Does a CRT (or LCD) spend more electricity to > make a white pixel than a black one, or is on pretty much on? > > On Sun, Dec 21, 2008 at 4:03 PM, Mike Bigalke <[email protected]> > wrote: > > > > Holy Fonts, Batman! > > > --~--~---------~--~----~------------~-------~--~----~ Central West End Linux Users Group (via Google Groups) Main page: http://www.cwelug.org To post: [email protected] To subscribe: [email protected] To unsubscribe: [email protected] More options: http://groups.google.com/group/cwelug -~----------~----~----~----~------~----~------~--~---
