Surgical lamp for contrast imaging of biological tissues

The theoretical, design, technological and software aspects of creating a dynamically controlled LED surgical lamp for contrast visualization of biological tissues during surgical operations are considered. The concept of design a surgical lamp, which combines white light illumination and dynamic control colored illumination, is proposed. It allowed both to reach high-quality illumination of the operational field and to improve the contrast of visualization of different biological tissues and objects. An optical system of the lamp, which allows achieving maximum and uniform illumination and provides uniform color mixing all over the operating field, is considered. Surgical lamp used both phosphor-conversion white LEDs for general illumination and monochrome AlInGaN, AlGaInP LEDs for precision control of color illumination. The developed software allows you to independently change the intensity of six spectral LED components: blue (460 nm), cian (505 nm), green (530 nm), lime (550 nm), orange (590 nm) and red (630 nm) to synthesize colored lighting in wide chromaticity scale. Also, within a wide range, it is possible to change the luminance and color temperature of the general illumination from white phosphor LEDs. Color and luminance evels are controlled by pulse-width modulation of the LED current. The light parameters of the surgical lamp are set by remote computer connected to the lamp via Bluetooth. To determine optimum illumination conditions for contrast visualization, optical characteristics of different biological tissues in combination with color LED emission are investigated. As a result, the experiments on animals showed the contrast of biological tissues imaging increases when they were illuminated with specially selected spectra emitted by developed lamp.