Advanced Imaging


Advanced Imaging Magazine

Updated: January 12th, 2011 10:01 AM CDT

Making a Splash in Optics

Autofocus liquid lenses provide variable focal lengths with no moving parts
Liquid lens technology
© Varioptic
Liquid lens technology is characterized by a very wide range of focal lengths that enable very close focus, high optical quality, fast and consistent response, and are very robust with no moving parts to wear or break.
The liquid interface
© Varioptic
The liquid interface is in contact with a conical metallic part insulated by a thin film. When an electrical voltage is applied charges accumulate on both sides of the film applying a force to the place where the interface rests. This becomes deformed and assumes a convex shape. The effect is rapid but also very reversible because the system has a very weak hysteresis.

By Nathalie Combrousse, Varioptic

Medical: Endoscopes, fiberscopes and dental cameras rely on the user to manually adjust the focus. A reliable autofocus allows for faster and less tedious handling of these tools. The requirements on the auto-focus system are primarily very close distance to focus (below 5cm, often below 1cm); reliability, especially compliance with medical environmental targets; silent operation, so it is not uncomfortable for the patient.

Low-vision systems also are being designed to help people with reduced vision (perhaps from glaucoma or cataracts). These may be handheld or fixed, for manual use or computer-assisted. They require autofocus to capture the target scene or image prior to displaying it back with the required improvements.
Given the usage scenario, a very high level of repeatability and reliability is expected from the autofocus actuator, along with the ability to focus at very close distances (below 10cm).

Nathalie Combrousse joined Varioptic (Lyon, France) as marketing communications manager in 2006. She has 18 years of international management experience in business-to-business and consumer marketing. She can be reached at Nathalie.combrousse

Subscribe to our RSS Feeds