Sufficient lighting is sometimes required when surgeons watch the mediastinum through the 7x7cm thoracic window in
video-assisted thoracoscopic (VATS) lobectomy. It is thus important to develop the "ultimately localized solid-statelighting"
because the distance between the window and the surface of the lung is as short as 4-5 cm. Our new idea was to
place the module composed of red, green and blue light emitting diodes (RGB LEDs) at the tip of the retractor.
Compared to a conventional endoscopic lighting consisting of halogen lamp, this method has lead to the bright and
shadowless illumination within the entire thoracic cavity since the white RGB LEDs are emitted unidirectionally from
the cylinder-shaped camera component, moving the shadows from the surgical instruments to the side of the incision. It
also should be noted that we found an effective principle for controlling the color rendering of each biomaterial through
the synthesis of LED lighting spectra, by which the visual performance of surgeons can be coordinated. Therefore, we
believe that "medical RGB LEDs" will contribute to the safe operation, and will be developed to a standard lighting
system in clinical settings with bright surgical fields in the near future.