A colored glass or other transparent material used to select the wavelengths of light allowed to reach a photosensitive material.

Camera lens filters are a photography accessory that are attached over the lens of a camera. They come in different shapes and forms, including polarizing filters to reduce glare and improve saturation, or simple UV/haze filters to provide extra protection for the front of your lens. The most commonly used filters for digital photography include polarizing (linear/circular), UV/haze, neutral density, graduated neutral density and warming/cooling or color filters.

The purpose of camera lens filters is to adjust the way that light comes through the lens and reaches the film or the sensor and to produce effects that cannot be achieved in the darkroom or through photo editing techniques.