PROBLEM TO BE SOLVED: To estimate barrier information being more suitable to a user using mobile equipment.SOLUTION: Light emitted from blue, green, and red laser diodes 1, 2, 3 is generated in a beam-like form by collimator lens 4a, 4b, and 4c, respectively, and a white laser beam is generated by making a predetermined wave length transmit and reflect by dichroic prisms 5, 6, and 7 so as to be synthesized. Since the white laser beam thus generated is radiated in high light intensity in a predetermined range, the light reflected by a reflector aggregate mounted with an element mirror having areas different each other can be brightly projected up to a far distance by one element mirror with one fixed star at a predetermined position. Moreover, the real starry sky can be expressed by the configuration in which the brightness and the color phase are changed for each fixed star.SELECTED DRAWING: Figure 1
