Light field

About: Light field is a research topic. Over the lifetime, 5357 publications have been published within this topic receiving 87424 citations.

On the possibility of almost complete self-squeezing of strong electromagnetic fields

Abstract: The propagation of quantized electromagnetic fields through optically isotropic media with cubic optical nonlinearity is considered. Analytical solutions are presented in closed form showing that the light field can emerge from the medium in a squeezed quantum state. A detailed numerical analysis of the results is performed and presented graphically. Over 90 per cent of the squeezing permitted by quantum-mechanical theory is achieved in this way. The dependence of the squeezing effect on the polarization state of the field and the nonlinear molecular parameters is also discussed.

Observation and simulation of an optically driven micromotor

Abstract: In the realm of low Reynolds number flow there is a need to find methods to pump, move and mix minute amounts of analyte. Interestingly, micro-devices performing such actuation can be initiated by means of the light–matter interaction. Light induced forces and torques are exerted on such micro-objects, which are then driven by the optical gradient or scattering force. Here, different driving geometries can be realized to harness the light induced force. For example, the scattering force enables micro-gears to be operated in a tangential setup where the micromotor rotors are in line with an optical waveguide. The operational geometry we investigate has the advantage that it reduces the complexity of the driving of such a device in a microfluidic environment by delivering the actuating light by means of a waveguide or fiber optic. In this paper we explore the case of a micromotor being driven by a fiber optically delivered light beam. We experimentally investigate how the driving light interacts with and diffracts from the motor, utilizing two-photon imaging. The micromotor rotation rate dependence on the light field parameters is explored. Additionally, a theoretical model based on the paraxial approximation is used to simulate the torque and predict the rotation rate of such a device and compare it with experiment. The results presented show that our model can be used to optimize the micromotor performance and some example motor designs are evaluated.

Functional vision testing using light field displays

Abstract: Systems and methods for performing visual field testing using light field displays are described. The light field display ( 201, 202; 801; 504; 601 - 604; 704; 801 ), that can correct for the focus and cylindrical refractive error of the subject, can be used to perform a variety of visual field testing strategies by rendering visual stimuli to the eye ( 203 ). The light field display may be included near the subject's eye, or reimaged by a relay optical system ( 802 ). Several embodiments of head and arm mounted systems ( 711; 704 ) including a near eye light field display ( 704 ) are presented.

Apparatus and method for acquiring 4D light field of scene

Abstract: A camera acquires a 4D light field of a scene. The camera includes a lens and sensor. A mask is arranged in a straight optical path between the lens and the sensor. The mask including an attenuation pattern to spatially modulate the 4D light field acquired of the scene by the sensor. The pattern has a low spatial frequency when the mask is arranged near the lens, and a high spatial frequency when the mask is arranged near the sensor.

System and method for feature-based light field morphing and texture transfer

Abstract: A “light field morpher,” as described herein, provides a computationally efficient system and method for image-based three-dimensional (3D) morphing and texture transfer of 3D objects by morphing “light fields” or “lumigraphs,” associated with source and target 3D objects. The light field morpher is applicable to morphing of objects having either or both Lambertian, or non-Lambertian surfaces, including surfaces having complex properties such as fur, subsurface scattering, and hypertextures, without the need for object modeling, or otherwise recovering detailed object geometry. Light field morphing begins by first specifying corresponding 2D and 3D feature elements, such as, “feature lines,” “feature polygons,” and “background edges,” in the input light fields representing the source and target light fields. Once the feature elements have been specified, “ray-space warping” of both light fields then warps those light fields to produce feature alignment. These warped light fields are then blended to produce a light field morph.