Apparatus for photodynamic diagnosis

A device for “in vivo” diagnosis having

• an illumination system, which is provided with at least one light source,
• a light delivering unit (2,5,21) which directs the light of said illumination system at a to-be-diagnosed tissue area (7), and
• an imaging, image-recording and image-transmitting unit (31,32,4,8) which images light coming from said tissue area (7) in a proximal image plane (13), with a net spectral transmittance Ti1(λ) of said light delivering unit being provided with a first pass region, which is adapted to a fluorescence excitation spectrum of said tissue area, and with a second pass region, and a net spectral transmittance Tb(λ) of said imaging unit being provided with a first pass region, which is adapted to a fluorescence spectrum of said tissue area,
• characterized by the fact that the net spectral transmittance Ti1(λ) of said light delivering unit is provided with a second pass region, a wavelength range of which lies between wavelengths of said fluorescence excitation spectrum and wavelengths of said fluorescence spectrum,
• that the net spectral transmittance Tb(λ) of said imaging unit is provided with a second pass region, which lies in a same wavelength range as said second pass region of said light delivering unit, and
• with a net transmittance of the device comprising said light delivering unit and said imaging unit having a spectral transmittance of more than 5% in said wavelength range.

A device for in vivo diagnosis of tissue, comprising:

• an illumination system,
• a light delivering unit having a first net spectral transmittance which overlaps with a fluorescence excitation spectrum of the tissue, and
• an imaging, image-recording and image transmitting unit having a second net spectral transmittance which overlaps with a fluorescence emission spectrum of the tissue, wherein
• the first and second net spectral transmittances overlap with each other such that a fluorescence image and a direct image of the tissue are both observable.