Abstract: A prism and light transmitter module includes a prism holder, a light transmitter, a prism module, a drive circuit board, a shield, and a fixing assembly. The light transmitter is configured to emit or receive a light beam along a light axis. The prism module includes an inclined plane and is disposed within the prism holder with the inclined plane exposed. The drive circuit board is disposed above the inclined plane, and intersects with the light axis at a first angle. The shield is disposed on the drive circuit board. The fixing assembly connects to the prism holder, is configured to fix the drive circuit board, and includes a hole through which the light transmitter is exposed. A binocular capable of measuring distance includes a first optical system and a second optical system. The first optical system or/and the second optical system include the prism and light transmitter module.

Abstract: A prism module includes a first prism including a first surface, a second surface and a third surface, a roof prism including a roof surface and a fourth surface, a second prism including a fifth surface, a sixth surface and a seventh surface, and a third prism including a light access surface, a first reflecting surface and a second reflecting surface. A light source is disposed above the second prism and adjacent to the first and the roof prisms. A light beam emitted by the light source enters and is reflected by the third prism, enters the second prism through the seventh surface, passes through the sixth surface, enters the first prism through the third surface, and is reflected by the second surface to leave the prism module. The light beam leaving the prism module is parallel to a baseline passing through the first, the second and the fourth surfaces.

Abstract: A prism and light transmitter module includes a prism holder, a light transmitter, a prism module, a drive circuit board, a shield, and a fixing assembly. The light transmitter is configured to emit or receive a light beam along a light axis. The prism module includes an inclined plane and is disposed within the prism holder with the inclined plane exposed. The drive circuit board is disposed above the inclined plane, and intersects with the light axis at a first angle. The shield is disposed on the drive circuit board. The fixing assembly connects to the prism holder, is configured to fix the drive circuit board, and includes a hole through which the light transmitter is exposed. A binocular capable of measuring distance includes a first optical system and a second optical system. The first optical system or/and the second optical system include the prism and light transmitter module.

Abstract: A prism module includes a first prism including a first surface, a second surface and a third surface, a roof prism including a roof surface and a fourth surface, a second prism including a fifth surface, a sixth surface and a seventh surface, and a third prism including a light access surface, a first reflecting surface and a second reflecting surface. A light source is disposed above the second prism and adjacent to the first and the roof prisms. A light beam emitted by the light source enters and is reflected by the third prism, enters the second prism through the seventh surface, passes through the sixth surface, enters the first prism through the third surface, and is reflected by the second surface to leave the prism module. The light beam leaving the prism module is parallel to a baseline passing through the first, the second and the fourth surfaces.

Abstract: A lens assembly includes a stop, a first lens, a second lens and a third lens, all of which are arranged in sequence from an object side to an image side along an optical axis. The first lens is a plano-convex lens with positive refractive power and includes a convex surface facing the object side. The second lens is with negative refractive power. The third lens is with positive refractive power and includes a convex surface facing the object side. The third lens satisfies 0<f3/f<1, wherein f3 is an effective focal length of the third lens and f is an effective focal length of the lens assembly.