Definition of absorbing wedge

Meadowlark Optics - Wave Plates 6/24 LB 2024

Photonics Dictionary

absorbing wedge: An absorbing wedge is an optical device used to control the intensity of light passing through it by absorbing a portion of the light. It is typically used in experiments and optical systems where precise control of light intensity is required. An absorbing wedge is a type of optical filter that has a variable thickness of absorbing material, creating a gradient in absorption across its length. This design allows for a gradual change in light intensity as the light passes through different parts of the wedge.

Gradient absorption: The thickness of the absorbing material increases gradually from one end of the wedge to the other, resulting in a corresponding gradient in the amount of light absorbed.

Light control: By moving the wedge or changing the position of the light beam along the wedge, one can adjust the amount of light passing through, allowing for precise control over light intensity.

Materials: Absorbing wedges are typically made from optical glass or plastic embedded with a light-absorbing dye or coating that attenuates light.

Applications:

Spectroscopy: Used to control light intensity in spectrometers and other optical instruments.

Photography and imaging: Helps in reducing light intensity for cameras and sensors to prevent overexposure.

Laser systems: Used to attenuate laser beams to safe or required levels without distorting the beam profile.

Example: In a spectroscopic experiment, an absorbing wedge might be placed in the path of a light source to gradually reduce the intensity of light entering a sample chamber. By adjusting the position of the wedge, the scientist can fine-tune the light intensity to the optimal level needed for accurate measurements without saturating the detector.