Question
State uses of concave lens.
✓
Answer
- Concave lenses are used for proper working of medical equipment, scanner, CD player – the instruments that employ laser rays.
- One or more concave lenses are used in a small safety device, fitted in the peep hole in a door, due to which we can see a large area outside the door.
- Concave lenses are used in spectacles to correct nearsightedness (myopia).
- A concave lens is used to spread light emitted by the small bulb in a torch over a wide area.
- A concave lens is used in front of the eyepiece or inside the eyepiece fitted in a camera, telescope and microscope – the instruments employing convex lenses.
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