The correct answer is: B. Greater than
The acceptance angle is the maximum angle of incidence at which light can be coupled into an optical fiber and still be guided along the fiber. If the angle of incidence is greater than the acceptance angle, the light will not be guided along the fiber and will be lost.
The acceptance angle is determined by the refractive indices of the fiber core and cladding materials. The refractive index is a measure of how much light bends when it passes from one material to another. The refractive index of the core material is higher than the refractive index of the cladding material, which causes light to bend as it enters the fiber. The angle of incidence is the angle between the incident ray and the normal, which is a line perpendicular to the fiber surface. The acceptance angle is the maximum angle of incidence at which light can be coupled into the fiber and still be guided along the fiber.
If the angle of incidence is greater than the acceptance angle, the light will not be guided along the fiber and will be lost. This is because the light will not bend enough to enter the fiber core. The light will instead reflect off of the fiber surface and be lost.
The acceptance angle is an important parameter in the design of optical fibers. It determines the maximum angle at which light can be coupled into the fiber and still be guided along the fiber. The acceptance angle is also important in the design of fiber optic connectors. The fiber optic connector must be designed to couple light into the fiber at an angle that is less than or equal to the acceptance angle.