Abstract: A lighting module for illuminating cultivated crops in indoor farming comprises at least one monolithic efficiency enhancing optical element (EEOE) further comprising: (a) a front portion comprising a spectrum conversion layer; (b) an optically transparent middle body portion having at least one light source embedded there within and configured to emit spectrally controllable radiation; and (c) a back portion configured to reflect the radiation emitted by the spectrum conversion layer to the cultivated crops. The back portion has a central area being adjacent to the optically transparent middle body portion configured for reflecting radiation propagating within the optically transparent middle body portion and a peripheral area configured for reflecting radiation emerged from the optically transparent middle body portion via the side surface.

Abstract: A lighting module for illuminating cultivated crops in indoor farming comprises at least one monolithic efficiency enhancing optical element (EEOE) further comprising: (a) a front portion comprising a spectrum conversion layer; (b) an optically transparent middle body portion having at least one light source embedded there within and configured to emit spectrally controllable radiation; and (c) a back portion configured to reflect the radiation emitted by the spectrum conversion layer to the cultivated crops. The back portion has a central area being adjacent to the optically transparent middle body portion configured for reflecting radiation propagating within the optically transparent middle body portion and a peripheral area configured for reflecting radiation emerged from the optically transparent middle body portion via the side surface.

Abstract: Methods and apparatus are provided for reducing cross-talk and jitter caused by track offsets in multi-beam optical disks. The method and apparatus involve using split detectors and cross-talk cancellation algorithms in the multi-element photodetector of the multi-beam optical disks. The cross-talk cancellation algorithms are applied according to the value of the track offset as a function of the track pitch.

Abstract: A device to be used with an existing eye-drop dispenser in order to assist the user in the self-administration of eye medication in the form of eye drops. The device comprises of a concave mirror, attached to the eye-drop container in a position where the mirror is at an angle approximately 35 degrees from the vertical axis of the container. When the reflected image of the eye is in focus, the eye-drops dispensed from the container reaches the correct area of the eye while an enlarged image of the eye is clearly visible during the process.

Abstract: Methods and apparatus are provided for reducing cross-talk and jitter caused by track offsets in multi-beam optical disks. The method and apparatus involve using split detectors and cross-talk cancellation algorithms in the multi-element photodetector of the multi-beam optical disks. The cross-talk cancellation algorithms are applied according to the value of the track offset as a function of the track pitch.

Abstract: A switchable liquid crystal diffractive element for use in an optical drive capable of reading multiple tracks of an optical disk simultaneously, and writing or erasing at least one track of the optical disk is disclosed. When the liquid crystal diffractive element is in an “on” state, it splits an incident beam into multiple beams suitable for simultaneously reading multiple tracks of an optical disk. When the liquid crystal diffractive element is in an “off” state, it permits an incident beam to pass through without being split, for writing to an optical disk. Embodiments are disclosed that use multiple electrodes to create switching and non-switching regions of a liquid crystal element to form a switchable phase grating, and that use a single switching liquid crystal element and a non-switching grating, or a birefringent non-switching grating, to form a switchable diffractive element.

Abstract: The present invention provides an optical system having a read mode, during which multiple tracks of an optical disk are simultaneously read, and a write mode, during which data is written to at least one track of the optical disk. The multiple light beams employed during read mode may be generated by a single laser diode operated at low power used in combination with a diffractive element, multiple laser diodes, or combinations thereof.

Abstract: A tri-focal diffractive lens defining three foci, for viewing a band of light having a representative wavelength of .lambda., including a diffractive surface having a number of optical heights, h.sub.o, wherein the difference between the highest and the lowest optical heights is, modulo .lambda., substantially different from .lambda./2, wherein each of the foci receives at least 20% of light incident on the lens.

Abstract: A diffractive optical element and a method to produce same is disclosed. The optical element comprises a base and at least first and second phase zones wherein the first phase zone comprises a first multiplicity of steps and the second phase zone comprises a second multiplicity of steps and wherein the first multiplicity and the second multiplicity of steps are different. The method to produce the diffractive optical element of the present invention includes the step of defining a collection of masks for creating stepped phase zones wherein at least one of the collection of masks partially masks out at least one phase zone such that the at least one phase zone will be partially etched.

Abstract: There is disclosed a diffractive optical element and a method to produce same wherein the element comprises a base and at least one phase zone comprising an arbitrary multiplicity M of steps of generally identical step height, wherein M is not a power of 2. The method includes the steps of defining a basic depth unit equivalent to a zone height divided by M, defining a depth sequence of N depths wherein N is the smallest integer greater than log.sub.2 M such that each of the M steps can be produced by at least one linear combination of the N depths, defining N masks herein each mask enables the optical element to be processed to one of the N depths and wherein for each mask, the steps to be processed are those which have the one of the N depths in its linear combination and serially utilizing each of the N masks for processing of the optical element.