| abstract |
A method and apparatus for autofocus on a target layer contained within a microplate well is provided. The instrument is capable of optically sensing a reference point on the underside of a microplate. This reference point is then used to focus light onto a target layer within the microplate well, the target layer having a location that is in defined relation to the reference point. The reference point is either a surface of the bottom of the microplate well or is an optically detectable mark on the underside of the microplate. In an alternate embodiment, a light position sensitive detector is used to enable deterministic autofocus for a plurality of wells on a microplate. |