Page 176 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

1 Outer Casing

• The TV’s exterior is typically made of plastic or metal and serves as a protective casing for the internal
components.

• The design of the outer casing contributes to the aesthetics and overall appearance of the TV.
2 Display Panel
• The display panel is the heart of the LED TV and is responsible for producing images. Common types of
display panels include LCD (Liquid Crystal Display) and OLED (Organic Light Emitting Diode).
• The display panel consists of a matrix of pixels that can change colour and brightness to form images.
3 LED Backlighting
• LED TVs use light-emitting diodes (LEDs) for backlighting. These LEDs are positioned behind the display
panel.
• There are two main types of LED backlighting: edge-lit and direct- lit. Edge-lit LEDs are placed along the edges
of the screen, while direct-lit LEDs cover the entire back panel.

4 Colour Filters and Liquid Crystal Layer
• Each pixel on the display panel is associated with red, green, and blue colour filters.
• In LCD panels, a layer of liquid crystals is present, which controls the passage of light through each pixel.
When an electric current is applied, the liquid crystals adjust to regulate the amount of light, determining the
colour and brightness of each pixel.
5 Local Dimming (if applicable)

• Some LED TVs feature local dimming technology, allowing dynamic adjustment of the backlight in different
areas of the screen. This enhances contrast by controlling the amount of light in specific regions.
6 Image Processing Circuitry

• LED TVs have built-in processors responsible for image processing tasks. This includes upscaling lower-
resolution content, adjusting contrast and colour levels, and managing motion processing to reduce motion
blur.
7 Audio Components
• LED TVs include audio components such as amplifiers, speakers, and audio processing software to deliver
sound. The placement of speakers can vary, with some TVs having front-facing speakers, while others have
downward or rear-facing speakers.
8 Power Supply and Circuit Boards

• The TV includes a power supply unit to convert electrical power for the various components.

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CITS : E & H - Electronics Mechanic - Lesson 100 - 107