Patent ID: 7924425
Filing Date: 2011-04-12
Classification: G01N

Abstract:
1. A spatially selective fluorescence detection system comprising: an optical fiber; and a ball lens mounted adjacent to one end of the optical fiber for receiving an emitted light from a spatially selected volume, the ball lens having a diameter larger than a diameter of the optical fiber, the ball lens and the one end of the optical fiber being separated by a first distance, the first distance being greater than a radius of the ball lens so that the light emitted from the spatially selected volume and received by the ball lens converges onto the one end of the optical fiber, wherein the first distance from the ball lens to the optical fiber is determined by positioning the spatially selected volume, treated as a point source, relative to the ball lens such that a circle of transmitted light defined by the intersection of a marginal transmitted ray and a caustic has a diameter equal to that of the optical fiber.