The closer the color rendering index of the surgical shadowless lamp is to the sunlight, the higher the color reproduction value of the object, the better, so that the operator (doctor) can see the bed surface better and make the operation process smoother! The color rendering of the object by the light source The ability is called color rendering, which is compared with the appearance color of the object under the same color temperature reference or reference light source (incandescent lamp or painting light). The spectral content emitted by the light determines the light color of the light source, but the same light color can be composed of many, a few or even only two monochromatic light waves, and the color rendering of each color is also very different. Light sources of the same light color have different spectral compositions, and light sources with a wider spectral composition are more likely to provide better color rendering quality. When there is little or lack of the main wave reflected by the object under the reference light source in the light source spectrum, the color will produce obvious color shift (colo shift). The greater the degree of chromatic aberration, the worse the color rendering of the light source. The color rendering index coefficient (Kaufman) is still a common method for defining the color rendering of light sources.