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Digital Frame Cameras Based on Area Arrays


 Digital Frame Cameras with Area Arrays in Satellite Remote Sensing

  1. What it is

    • A digital frame camera is like a normal camera (phone or DSLR) but used in satellites.

    • It takes a picture of the Earth in one shot (a frame), instead of scanning line by line.

  2. Area Array Sensor

    • Inside the camera, there is an area array — a grid of tiny light-sensitive cells called pixels.

    • Example: 4000 × 4000 pixels → captures a square image of the Earth.

    • Each pixel records the amount of reflected light from the ground.

  3. How it works in satellites

    • The satellite moves in orbit.

    • The camera clicks frames at intervals.

    • These frames are stitched together to create a large map of Earth's surface.

  4. Advantages

    • High resolution → small ground details (like roads, fields, buildings) can be seen.

    • Fast capture → takes a full area at once, not slowly scanning.

    • Accurate geometry → less distortion compared to scanning sensors.

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