Abstract: An auto-focus system employing a tunable liquid crystal lens is provided that collects images at different optical power values as the liquid crystal molecules are excited between a ground state and a maximum optical power state tracking image focus scores. An image is acquired at a desired optical power value less than maximum optical power established with the liquid crystal molecules closer a fully excited state than the maximum optical power state having the same image focus score. This drive signal employed during image acquisition uses more power than was used to achieve the same optical power value during the auto-focus scan, while actively driving the liquid crystal molecules is fast. A pause due to image transfer/processing delays after acquisition is employed to allow slow relaxation of the liquid crystal molecules back to the ground state in preparation for a subsequent focus search.

Abstract: A liquid crystal optical device is provided. The optical device includes a liquid crystal cell controlling optical properties of light passing therethrough and has: a liquid crystal layer, a planar electrode located to one side of said liquid crystal layer; an electric field control structure located to the opposite side of the liquid crystal layer; and a wavefront adjustment structure configured to provide optical phase front adjustment. In some embodiments the wavefront adjustment structure is a conductive floating electrode. In other embodiments the wavefront adjustment structure is a weakly conductive structure having spatially variable sheet resistance. In other embodiments the wavefront adjustment structure a weakly conductive structure having spatially variable sheet resistance having a frequency dependent characteristic.

Abstract: A wafer level camera module can be easily connected to a host device via mounting surface contacts. The module includes an electrically controllable active optical element and a flexible printed circuit that provides electrical connection between the optical element and surface conductors on a mounting surface of the module. The surface conductors can be a group of solder balls, and the module can have another group of solder balls that make connection to another electrical component of the module, such as an image sensor. All of the solder balls can be coplanar in a predetermined grid pattern, and all of the components of the device can be surrounded by a housing such that the camera module is an easily mounted ball grid array type package.

Abstract: Variable liquid crystal devices for controlling the propagation of light through a liquid crystal layer use a frequency dependent material to dynamically reconfigure effective electrode structures in the device. The drive signal source uses pulse-width modulation to set a frequency and an amplitude of the drive signal.

Abstract: An electrically controllable optical lens apparatus makes use of fixed lenses and an active optical element together in a lens enclosure. The enclosure may be a barrel structure that is easily mounted to a camera device having an image sensor. The active optical element, such as a tunable liquid crystal lens, receives an electrical signal from the camera device via electrical conductors integral with the lens enclosure that provide electrical pathways between the active element on the interior of the enclosure and surface contacts on the camera device. The enclosure may be a two-piece structure, and the electrical conductors may be attached to either piece of the structure. The lens enclosure may also be threaded for attachment to the camera device. The electrical conductors may also use spring loaded contact portions or molded interconnect devices.

Abstract: A liquid crystal lens or beam steering device is made by programming alignment surfaces of the LC cell walls using a programming field to align the alignment surface molecules before fixing them. By setting the desired pre-tilt, the lens can operate in the absence of the control field, and power consumption by the control field can be reduced.

Abstract: An electrode structure is proposed for controlling a spatially non-uniform electric field driving a tunable liquid crystal lens or beam steering device. The spatially non-uniform electrode structure enables the generation of a predetermined spatially non-uniform electric field profile where complex capacitive coupling between multiple different electrically floating neighboring electrode segments is employed for the generation of the electrical field of desired form by supplying an initial electric potential to a limited number of electrodes.

Abstract: A wafer level method of manufacturing a liquid crystal optical device removes the need for a rigid barrier fillet while minimizing any risk of contamination of the liquid crystal. An uncured adhesive may be deposited on a bottom substrate and partially cured to form a liquid crystal barrier. After addition of the liquid crystal and a top substrate, the adhesive is fully cured to bond the substrate layers together. An uncured adhesive may be used together with the partially cured adhesive, and may be deposited separately or filled into an extracellular matrix surrounding a plurality of liquid crystal cells. The adhesive may be cured by a variety of means, including light that may be spatially modulated. One or both of the substrates may be deformed during assembly so as to create a structure with a lensing effect on light passing through the liquid crystal region.

Abstract: A tunable liquid crystal optical device defining an optical aperture and having a layered structure. The device includes a film electrode formed on a surface of a first substrate and covered by a second substrate, and a contact structure filling a volume within the layered structure and contacting the film electrode. The contact structure is located outside of the optical aperture and provides an electrical connection surface much larger than a thickness of the film electrode, such that reliable electrical connections may be made to the electrode, particularly in the context of wafer scale manufacturing of such a device.

Abstract: An auto-focus system employing a tunable liquid crystal lens is provided that collects images at different optical power values as the liquid crystal molecules are excited between a ground state and a maximum optical power state tracking image focus scores. An image is acquired at a desired optical power value less than maximum optical power established with the liquid crystal molecules closer a fully excited state than the maximum optical power state having the same image focus score. This drive signal employed during image acquisition uses more power than was used to achieve the same optical power value during the auto-focus scan, while actively driving the liquid crystal molecules is fast. A pause due to image transfer/processing delays after acquisition is employed to allow slow relaxation of the liquid crystal molecules back to the ground state in preparation for a subsequent focus search.

Abstract: A liquid crystal optical device has a layered structure with split liquid crystal layers having alignment surfaces that define in a liquid crystal material pre-tilt angles of opposite signs. Four liquid crystal layers can provide two directions of linear polarization. In the case of a lens, the device can be a gradient index lens, and the alignment surfaces can have a spatially uniform pre-tilt.

Abstract: A camera module and method for focusing a tunable lens configured to continuously vary its optical power in response to a drive signal. A drive circuit generates the drive signal so that the tunable lens performs a continuous scan of its optical power. An image sensor is configured to acquire light images passing through the tunable lens, and to convert the light images to image signals during the continuous scan. A processor is configured to generate focus scores of the acquired light images using the image signals during the continuous scan. The processor is configured to determine from the focus scores a peak focus score achieved or achievable, and to instruct the drive circuit to adjust the drive signal so that the tunable lens settles at a value of the optical power that corresponds to the peak focus score.

Abstract: A tunable liquid crystal lens employing a dual frequency liquid crystal material exhibiting a dielectric anisotropy about a crossover frequency at room temperature is provided. A tunable liquid crystal lens drive signal having low and high frequency components about the crossover frequency, applies a spatially modulated electric field to the dual frequency liquid crystal layer, wherein the differential root means square amplitude determines the optical power. Changing the differential root means square amplitude provides optical power changes under prevailing excitation conditions providing improvements in optical power change speed. Employing drive signal pulses can impart further optical power change speed improvements. A variety of tunable liquid crystal lens structures employing the proposed solution are described.

Abstract: A tunable liquid crystal optical device defining an optical aperture and having a layered structure. The device includes a film electrode formed on a surface of a first substrate and covered by a second substrate, and a contact structure filling a volume within the layered structure and contacting the film electrode. The contact structure is located outside of the optical aperture and provides an electrical connection surface much larger than a thickness of the film electrode, such that reliable electrical connections may be made to the electrode, particularly in the context of wafer scale manufacturing of such a device.

Abstract: A tunable liquid crystal optical device is described. The optical device has an electrode arrangement associated with a liquid crystal cell and includes a hole patterned electrode, wherein control of the liquid crystal cell depends on electrical characteristics of liquid crystal optical device layers. The optical device further has a circuit for measuring said electrical characteristics of the liquid crystal optical device layers, and a drive signal circuit having at least one parameter adjusted as a function of the measured electrical characteristics. The drive signal circuit generates a control signal for the electrode arrangement.

Abstract: A wafer level method of manufacturing a liquid crystal optical device removes the need for a rigid barrier fillet while minimizing any risk of contamination of the liquid crystal. An uncured adhesive may be deposited on a bottom substrate and partially cured to form a liquid crystal barrier. After addition of the liquid crystal and a top substrate, the adhesive is fully cured to bond the substrate layers together. An uncured adhesive may be used together with the partially cured adhesive, and may be deposited separately or filled into an extracellular matrix surrounding a plurality of liquid crystal cells. The adhesive may be cured by a variety of means, including light that may be spatially modulated. One or both of the substrates may be deformed during assembly so as to create a structure with a lensing effect on light passing through the liquid crystal region.

Abstract: Variable liquid crystal devices for controlling the propagation of light through a liquid crystal layer use a frequency dependent material to dynamically reconfigure effective electrode structures in the device. The drive signal source uses pulse-width modulation to set a frequency and an amplitude of the drive signal.

Abstract: Methods and apparatus for testing operation of a single or multiple tunable active optical device(s) operated by one or more driving electrodes are described Test methods and apparatus are provided for device testing without necessarily requiring direct physical contact with the driving electrodes Testing subjects devices to incident light along an optical path and to an external electric field applied to the device producing a dipolar charge distribution within the electrodes, causing the device to operate The effect of device operation on incident light is optically sensed The sensed effect is analyzed to identify device defects Test methods and apparatus are provided for testing multiple unsingulated devices during fabrication employing a strip contact structure having contact strips connected to multiple devices and extending to wafer edges, such that singulating devices leaves portions of the strip contact structure exposed on device dice edges providing electrical contacts in use.

Abstract: Variable liquid crystal devices for controlling the propagation of light through a liquid crystal layer use a frequency dependent material to dynamically reconfigure effective electrode structures in the device. The frequency of a drive signal that generates an electric field in the device may be varied, and the frequency dependent material has different charge mobilities for the different frequencies. At a low charge mobility, the frequency dependent material has little effect on the existing electrode structures. However, at a high charge mobility, the frequency dependent material appears as an extension of the fixed electrodes, and may be used to change the effective electrode structure and, thereby, the spatial profile of the electric field. This, in turn, changes the optical properties of the liquid crystal, thus allowing the optical device to be frequency controllable.

Abstract: Variable liquid crystal devices for controlling the propagation of light through a liquid crystal layer use a frequency dependent material to dynamically reconfigure effective electrode structures in the device. The frequency of a drive signal that generates an electric field in the device can be varied, and the frequency dependent material has different charge mobilities for the different frequencies. At a low charge mobility, the frequency dependent material has little effect on the existing electrode structures. However, at a high charge mobility, the frequency dependent material appears as an extension of the fixed electrodes, and can be used to change the effective electrode structure and, thereby, the spatial profile of the electric field. This, in turn, changes the optical properties of the liquid crystal, thus allowing the optical device to be frequency controllable.