Patent ID: 7939023

Claim:
An assay apparatus comprising: a sensor unit including an optical block having a sensing surface, disposed on an upper surface thereof, for detecting reaction of a sample, and a flow cell, secured to said upper surface, having a flow channel for flow of sample fluid containing said sample to said sensing surface; a light source for applying light to said optical block; a detector for optically measuring reaction of said sample on said sensing surface, said assay apparatus further comprising: an assay stage, having a stage surface for contacting a lower surface of said optical block, for supporting said sensor unit removably; an optical block retaining mechanism for retaining said sensor unit in a predetermined orientation on said stage surface by engagement with a housing for said optical block; said optical block retaining mechanism including a holder, wherein said holder is shiftable between a retaining position and an initial position, wherein in said retaining position, said holder which pushes vertically on the housing to place said lower surface of said optical block on said stage surface, wherein in said initial position, said holder releases vertical force on the housing to release said optical block from retention on said stage surface.