the first light capturing unit 24 a via the connection fiber 22 c the photocoupler 23 and the image transmission fiber 22 i as described above the reflected light which is the excitation light is blocked by the excitation light cut filter 25 so that only the fluorescence is made incident on the first light capturing unit 24 a in the above embodiment a lens unit 33 can be downsized the diameter of an insertion tube 31 can be reduced and the signal to noise ratio can be improved those effects are explained as follows in a confocal observation optical information from only a pinpointed area of each illuminated point needs to be captured accordingly a single mode fiber is adequate for the scanning fiber 32 used in the confocal endoscope apparatus in addition in a confocal observation a light beam with a thick diameter must be condensed by a condenser optical system that has a large numerical aperture as described above the numerical aperture of a standard single mode fiber is low and the diameter of the beam of excitation light emitted from the single mode fiber is not thick enough accordingly as shown in fig5 an optical enlargement system 33 e that expands the diameter of the excitation light beam generally needs to be included in a lens unit 33 on the other hand in the above embodiment because the diameter of the beam of excitation light emitted from the emission end of the scanning fiber 32 has adequate thickness the optical enlargement system 33 e is unnecessary consequently a lens unit.