Liquid Lens Technology

The liquid lens module is an electronically controllable variable focus system.

Cognex is the first company to release an industrial fixed-mount ID reader based on this new technology.

The liquid lens uses two iso-density liquids—oil is an insulator while water is a conductor. The variation of voltage leads to a change of curvature of the liquid-liquid interface, which in turn leads to a change of the focal length of the lens.

The following diagram shows how the liquid lens is constructed:

The key advantages of the liquid lens are its ruggedness (no moving parts), fast response times, good optical quality, low power consumption and size.

Advantages and Availability

The liquid lens can simplify installation, setup and maintenance by eliminating the need to manually touch the lens. Relative to other autofocus mechanisms, the liquid lens has extremely fast response times. It is also ideal for applications with reading distances that change from part to part or during part changeover.

DataMan 200 readers come with a three-position adjustable lens or are pre-installed with the liquid lens and can easily be configured with the standard DataMan Set Up Tool.