1. The document describes the working principles of light-emitting diodes (LEDs) and liquid crystal displays (LCDs). 2. It explains that in an LED, electrons recombine with holes in the PN junction, emitting light. In an LCD, an external voltage disturbs the molecular arrangement of the liquid crystals, allowing pixels to block or pass light. 3. The document also provides an overview of the key components and functioning of a cathode ray tube (CRT) computer monitor. It describes how an electron beam is deflected by electric fields to scan phosphorescent points on the screen and create a visible image.

1. Date
Expt. No. 18-9
Page No,
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2. Date
Expt. No. Page No,2
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3. Date
Expt. No. Page No3
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4. Date
Expt. No.
Page No.
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5. Datc
Expt. No. Page No.S
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6. Date
Page No.6
Expt. No.
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