Optics.org: Horten, Norway-based poLight AS, a developer of 0.5mm-thin reflowable autofocus actuated lenses for camera phones, announced raising of NOK100 million ($18.5M), in its series B round led by local Investinor fund with the participation of existing shareholders Viking Venture III AS, Alliance Venture Polaris AS and SINTEF Venture III AS. poLight’s round B of financing could be extended to NOK130M ($24.5M) in the second part of the year with additional investors joining the consortium.
poLight has been spun-off from Ignis ASA (acquired by Finisar) in 2009. poLight’s CEO Christian Dupont used to be Varioptic CEO before that.
poLight's TLens is said to be the first reflowable autofocus actuated lense with no moving parts and has "extremely small size (4.2mm x 4.2mm x 0.5mm), while achieving high optical quality (megapixel independent and HD compatible)". TLens allows "close-up macro Autofocus (<10 cm) and fast video Autofocus (10 times faster than traditional VCM)". Also, poLight’s "technology makes it possible to manufacture small camera modules at the wafer level, drastically reducing the cost of the TLENS and, as a result, the cost of camera modules". The lens transmittance is said to be over 95%.
When compared with VCM, today's dominating AF technology, TLens advantages are said to be wafer scale processing, reflowability up to 260C, speed (less than 1ms response time), and energy efficiency (1mW of power consumption).
poLight says it has already begun sampling the TLens with a high level of interest. poLight will not be manufacturing the devices itself. Instead it will be co-operating with “leading MEMS semiconductor suppliers”. It expects to enter qualification with customers in late 2011, with volume production starting in early 2012.
How it works:
An embedded a piezo on a thin glass membrane works an actuator. Underneath is positioned some polymer on a glass support. At “zero” volt, the piezo is in standby mode and does not apply any force to the thin glass. The light going through the two elements of glass and through the polymer is not deviated.
Once a voltage is applied (up to 30V), the piezo actuator forces the thin glass membrane to bend. This generates an optical power variation allowing focusing (click on picture to see a nice animation):
Update: Somebody in comments uploaded poLight's demo picture showing infinite focus on the left, 10cm - on the right: