nir-vana innovation network

A well-known Spanish university has developed a novel device for generating a micrometric lens array by the application of electric voltages to a set of comb-shaped intertwined electrodes, which allows controlling the shape and focus of the microlenses.
This technology can be applied for autostereoscopic devices (displaying three-dimensional images without using any special device) and plenoptic capture systems (multi-perspective image capture of 3D scenes), in addition to use as liquid crystal microlenses in general.

Microlens arrays are required increasingly for various applications. They are usually performed by means of slow and complex lithography processes, making the product considerably more expensive. Furthermore, these lenses cannot be modified after manufacture, with the subsequent drawbacks this entails. Some solutions propose the use of liquid crystal as a material for creating tunable microlenses with the voltage. Many proposals have serious limitations, such as limited optic power, low fill factor due to the circular aperture and generation of aberrations due to electric field distribution.

In order to overcome these limitations, a micrometric structure formed by several intertwined electrode combs arranged orthogonal to one another has been developed (see attachment). When out-of-phase voltages are applied between the combs, spherical microlens array is generated. These microlenses possess enormous optic power (small focal distances). Furthermore, the square aperture gives rise to arrays with a high fill factor (“fill factor”), making maximum use of the area and improving optic efficiency.

As a result of the individual control of each side of the microlens (by means of voltage), the shape and focus of the microlenses can be tuned. This property can be used in reducing aberrations by means of using specific voltages and phase differences. These advantages compared to existing solutions are of enormous commercial interest in the following generation of autostereoscopic devices based on integral imaging and on plenoptic capture systems, in which the square aperture and wide-range tunable focusing capacity provide a high added value.
Another field of application comprises micrometric-sized liquid crystal lenses. Such lenses have a number of applications, such as a fiber coupling, scanner, charge coupled device sensors (CCD), aberration control, autostereoscopic systems, image processing, etc.

The university is currently looking for potential partners interested in this innovative technology to work under technical cooperation agreement, license agreement or financial agreement, investing in the further development. The expected outcome of the collaboration includes completing the prototype, field testing, industrialising and commercialising the innovation.
Ideal partners would be companies manufacturing liquid crystals, microlenses, optic instruments, plenoptic photography or autostereoscopic devices.

Advantages & innovations

Innovative aspects: - Tunable liquid crystal microlens array. - Electrodes in the form of intertwined combs. - Several specific electrode structures and arrangements. - Intelligent control of the voltages applied to the electrodes. - Control of microlens shape and focus. - High fill factor with minimal edge effect (aberrations). Advantages: - Different microlens array shapes. - Electronically tunable microlenses. - Control of microlens shape and focus. - High fill factor with minimal edge effect (aberrations).

Stage of development

Under development/lab tested

Partner sought

- Manufacturers of liquid crystals, microlenses, optic instruments, plenoptic photography, and autostereoscopic devices to work under license or technical cooperation agreement in the completion of the prototype, field testing, industrialization and commercialization of the technology. - Investors interested in the technology to collaborate under financial agreement in order to develop the prototype and field-test it.