Shadowless lamp is a device that arranges high luminous intensity point light sources on a large circular lamp panel, allowing the point light sources to emit light from different angles. You can’t see the shadows formed by each point light source. Shadowless lamps are essential lighting equipment in hospital operating rooms, which are of great help to surgical safety, efficiency, quality, continuous work of the surgeon, and eye protection.

The composition of shadowless lamps

Shadowless lamps are generally composed of single or multiple lamp heads, which are fixed on a cantilever and can move vertically or cyclically. The cantilever is usually connected to a fixed connector and can rotate around it. The shadowless lamp adopts a disinfectable handle or a disinfected clamp (track) for flexible positioning, and has automatic braking and stopping functions to control its positioning, maintaining a suitable space above and around the surgical site. The fixing device of the shadowless lamp can be placed at a fixed point on the ceiling or wall, or on the track of the ceiling.

The working principle of shadowless lamps

Shadow is formed when light shines on an object. The shadows on Earth are different everywhere. Carefully observe the shadows under the electric light, and you will also find that the middle of the shadows is particularly dark, with slightly shallower surroundings. The particularly dark part in the middle of the shadow is called the umbra, and the gray part around it is called the penumbra. The occurrence of these phenomena is closely related to the linear propagation of light.

Due to the propagation of light along a straight line, shadows are formed when the light shines on an object. The shadow varies at different times and places, for example, a person’s shadow in the sunlight is shorter at noon and longer in the morning and evening.

The shadow of an object under a beam of light is particularly dark in the middle, known as the umbra, while the gray parts around it are called the penumbra. These phenomena are closely related to the linear propagation of light. It is obvious that the larger the area of the light source body, the smaller the umbra. When we light up an incandescent lamp around us, the umbra will completely disappear and the penumbra will also be invisible. People have made shadowless lamps based on the above principles.

A shadowless lamp is a circular arrangement of several lamps with high luminous intensity on a lamp panel, forming a large area of light source. In this way, there will be different angles of light shining on the operating table, which does not produce obvious umbra and ensures sufficient brightness of the surgical field of view, so it is called a "shadowless lamp".