Patent ID: 7604984

Claim:
A system comprising: a biosensor; and a label-free optical reader system which includes: a light source that outputs a first optical beam which is smaller than the biosensor and is scanned across the biosensor; a detector that collects a second optical beam reflected from the biosensor while the first optical beam is being scanned across the biosensor; and a processor that processes the collected second optical beam to obtain raw spectral/angular data that is a function of a position on the biosensor; and said biosensor has a waveguide formed from a substrate, a diffraction grating and a waveguide film, wherein the biosensor has at least one reference region on which target molecules cannot bind and at least one sample region on which the target molecules can bind, wherein the at least one reference region and the at least one sample region are formed in a predefined pattern, wherein the raw spectral/angular data associated with the at least one sample region is used to perform a label-free detection of a biomolecular binding event and the raw spectral/angular data associated with the at least one reference region is used to reference out spurious changes that can adversely affect the label-free detection of the biomolecular binding event, wherein said biosensor has at least one diagonal cut located at a diagonal angle across features which make-up the diffraction grating wherein the diagonal cut enables the use of a 1-dimensional beam scan to estimate both an x and y location of said biosensor relative to said label-free optical reader system.