Cameras, specifically DSLRs, primarily use mirrors to direct light from the lens to the optical viewfinder, allowing the photographer to see the image before taking the shot.
The Role of the Reflex Mirror in DSLRs
The key component using a mirror is found in DSLR (Digital Single-Lens Reflex) cameras: the reflex mirror.
- Position: It sits at a 45-degree angle directly behind the lens.
- Function: This mirror reflects the incoming light upward towards the viewfinder.
- Mechanism: Typically, it's a moving mirror that flips up out of the way when the shutter is released to allow light to reach the image sensor.
How it Works: A Step-by-Step Explanation
- Light Enters: Light passes through the camera lens.
- Reflection: The reflex mirror reflects this light upward.
- Viewfinder: The reflected light travels to a focusing screen and through a prism (or a series of mirrors in some models) in the viewfinder. This allows the photographer to see the exact image that will be captured.
- Taking the Picture: When the shutter button is pressed, the reflex mirror flips up, moving out of the light path.
- Exposure: The shutter opens, and the light then strikes the image sensor, capturing the image.
- Mirror Returns: The mirror returns to its original position after the exposure.
Summary
Essentially, the mirror in a DSLR camera acts as a light director, providing a real-time view through the lens to the photographer's eye. This allows for accurate framing and focusing before the image is captured by the sensor.
