Digital Frame Cameras Based on Area Arrays

Digital Frame Cameras with Area Arrays in Satellite Remote Sensing

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.
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.
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.
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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