Opening angle (disambiguation)

Opening angle stands for:

• Angle in optical systems that a point on the optical axis forms with the diameter of the entrance or exit pupil
• Duration of the opening of a valve in the valve control of four-stroke engines
• Angle of a cone in geometry , which denotes twice the angle between the surface lines and the axis of a rotary cone
• Axis angle for XY coincidence microphones (stereo microphones), d. H. the angle between the main microphone axes
• Directivity factor in antenna technology , d. H. the half width of an antenna

This is a disambiguation page for differentiating between several terms identified with the same word.