Patent ID: 8192686

Claim:
A bio-chip measurement apparatus for measuring fluorescence emitted from a bio-chip 11 in which at least one or more bio samples 14 are arranged on one surface of a thin rectangular parallelepiped-shaped substrate 12 , comprising: a bio-chip 11 ; a bio-chip holder 19 for supporting the bio-chip 11 ; an excitation light supply section 10 for allowing an excitation light emitted therefrom to be incident to a side face 13 of the substrate 12 so as to be totally reflected inside the substrate 12 to reach in the vicinity of the bio samples 14 ; a diffusion plate 21 disposed between the side face 13 of the substrate 12 and the excitation light supply section 10 for inducing diffusion of the light to be incident to the substrate 12 to allow the light totally reflected inside the substrate 12 to form a uniform evanescent field 17 over a wide range of area; a fluorescence detecting section 18 disposed above the substrate 12 for observing and detecting fluorescence emitted from the bio samples 14 through the evanescent field 17 formed by the light totally reflected inside the substrate 12 ; and an iris diaphragm 22 mounted at the upper and lower end portions of the side face 13 of the substrate 12 for preventing a diffusion light having an incidence angle smaller than the critical angle of total internal reflection from entering the inside of the substrate 12 .