For some fiber optic applications, like high-end endoscopy, light sources with high luminance are necessary. Currently,
short arc discharge lamps are being used. However, more and more LED solutions are trying to compete, but they can
not yet reach the performance obtainable by 300 W Xenon short arc discharge lamps. To make this field of application
accessible for solid state light sources, a new approach is necessary.
Diode lasers have rapidly advanced in the past years. This is particularly true for multimode laser diodes emitting at
around 445 nm wavelength. Single diodes emitting more than 1 W of optical power are already available. These laser
sources exhibit extremely high radiance, thus they can be focused onto very small areas. Phosphors placed near the focus
can result in high luminance sources. On the basis of this idea, a device has been developed to match the performance of a state of the art 300 W Xenon lamp system. An array of laser diodes is used to illuminate a phosphor plate which converts the blue pump light into yellow light. The converted light is collected and adapted to the application by a tapered TIR rod. To achieve a color point on the Planckian locus at 6000 K, the light of an LED emitting at around 460 nm is superimposed to the converted light.