Efficient Optical Arrangement for Illumination and Dectection of Label-Free Biosensors and Method to Reduce Interference Fringes in Label-Free Imaging

Abstract

An optical arrangement for illuminating a surface of a biosensor having a periodic surface grating structure. The arrangement includes a light source generating light, collimating optics for collimating the light from the light source, and a first reflecting surface (e.g., prism surface) receiving light from the collimating optics and directing incident light onto a surface of the biosensor and a second spatially separated reflecting surface receiving light reflected from the surface of the biosensor. The arrangement further includes telecentric optics (e.g., telecentric lens) receiving light from the second surface of the prism. The telecentric lens directs light onto an entrance slit of a spectrometer. The arrangement increases the light collection efficiency at the spectrometer as compared to prior art arrangements.

I claim: 
     
         1 . An optical arrangement for illuminating a surface of a biosensor comprising a photonic crystal biosensor having a periodic grating structure in the form of lines having a direction, comprising:
 a light source generating light;   collimating optics for collimating the light from the light source;   first and second spatially separated reflecting surfaces, wherein the first reflecting surface receives light from the collimating optics and directs incident light onto a surface of the biosensor and the second reflecting surface receives light reflected from the surface of the biosensor;   telecentric optics receiving light from the second reflecting surface; and   a spectrometer having an entrance slit receiving light from the telecentric optics.