An imaging system, includes: a laserlight source having a wavelength from 380 nm to 490 nm; and a beam guidance element, the laserlight source configured for generating an average surface power density of more than 10 W / cm2, the beam guidance element including a glass which has a quality factor F(436 nm)=S(436 nm)*(Abs0(436 nm)+Abs1(436 nm)) / k, wherein S(436 nm) is a thermality at a wavelength of 436 nm, Abs1(436 nm) is an additional absorbance in comparison to Abs0(436 nm) at a wavelength of 436 nm after an irradiation with a power density of 345 W / cm2 for 72 hours with a laser light having a wavelength of 455 nm, Abs0(436 nm) is an absorbance at a wavelength of 436 nm of a sample having a thickness of 100 mm without the irradiation, k is the thermal conductivity, and the quality factor F(436 nm) is <15 ppm / W.