Abstract: A backlight module includes a light guide plate (52), a light source (51), a reflecting sheet (53), a diffusion sheet (54), and a reflective polarizing beam splitter (57). The light guide plate includes a light input surface (521), a light output surface (522) adjacent to the light input surface, a reflecting surface (523) opposite the light output surface, and a number of microstructures (524) located on the reflecting surface. In the light guide plate, stress-induced birefringence is introduced to achieve a polarization state conversion, thereby facilitating efficient use of the light generated by the light source.

Abstract: A system for designing a free form reflector includes a user input interface (1), a free form reflector design unit (2), and a free form reflector output unit (3). The user input interface is configured for receiving various data associated with a desired free form reflector, via an input device. The free form reflector design unit is installed in a computer and configured for generating an optimum free form surface according to the input data by performing a non-uniform rational basis splines (NURBS) algorithm, a merit evaluation function, and a differential evolution (DE) algorithm. The free form reflector output module is configured for generating a free form reflector according to the optimum free form surface and outputting the free form reflector, in the form of a computer-aided design (CAD) drawing, to a display and/or a printer. A related method is also disclosed.

Abstract: A light guide device (52) includes a light guide substrate (520) and a sub-wavelength grating (527). The light guide substrate has a light input surface (521), a light output surface (522) adjacent to the light input surface (521), a bottom surface (523) opposite to the light output surface (522). In the light guide plate, stress-induced birefringence is introduced to achieve the polarization state conversion. The SWG 527 located on the light output surface includes a top layer (525) and a bottom layer (526). The SWG 527 is configured to work as a reflective polarizing beam splitter, consistent with the principle of rigorous coupled-wave theory.

Abstract: An exemplary zoom lens system includes a negative first lens group and a positive second lens group. The first lens group includes a meniscus-shaped first lens with negative refracting power and a second lens with positive refracting power. The first lens has a concave surface facing an image side. The second lens group includes an aperture stop, a biconvex third lens with positive refracting power, and a meniscus-shaped fourth lens with negative refracting power. The fourth lens has a concave surface facing an object side. The first lens, the second lens, the aperture stop, the third lens and the fourth lens are aligned in that order from the object side to the image side.

Abstract: A backlight module (70) includes a light guide plate (72), a light source (74), a micro reflector array (723), and a reflector (76). The light guide plate includes a light input surface (722) facing the light source, a light output surface (724) adjacent to the light input surface, and a reflective surface (726) opposite to the light output surface. The light source and an emitting surface (744) thereof both face the light input surface. The micro reflector array and the reflector are configured for cooperatively coupling a first portion of the light beams into the light input surface via any corresponding microgap and reflecting a second portion of the light beams into the light guide plate at a location distant from the light source.

Abstract: A Fourier transform lens system includes a first lens group having positive power, a second lens group having positive power, and a third lens group having negative power, all arranged on a common optical axis in that sequence. The first lens group includes a first positive meniscus lens, and a negative meniscus lens adjacent to the second lens group. The first positive meniscus lens has a concave lens surface facing toward a concave lens surface of the negative meniscus lens. The second lens group includes at least one bi-convex lens. The third lens group includes a second positive meniscus lens adjacent to the second lens group and a bi-concave lens. The second positive meniscus lens has a convex lens surface facing toward the second lens group. The Fourier transform lens system satisfies the following conditions: (1) 0.8<f2/f<1.4; (2) ?1.3<R12F/f<?0.7; (3) 0.35<R31F/f<0.75; and (4) 0.3<R32R/f<0.7.

Abstract: A backlight module includes a light guide plate having an incident surface, an emitting surface adjacent to the incident surface, and a reflective surface opposite to the emitting surface. At least one light source is disposed adjacent the incident surface. The light source has a luminescent surface; and at least one reflecting device is disposed adjacent the light source. The reflecting device has a reflective surface facing the incident surface. At least one semi-transmissive and semi-reflective film disposed on the incident surface of the light guide plate. The semi-transmissive and semi-reflective film and the reflecting device together are disposed for cooperatively reflecting some (i.e., a fraction) of the light beams emitted from the light source and redirecting the fraction of the light beams into the light guide plate through the incident surface, distant from the light source.

Abstract: A light guide device includes a main body having a first incident surface, a second incident surface, an emitting surface, a reflecting surface and a plurality of first microstructures. The first incident surface is opposite to the second incident surface. The emitting surface extends from the first incident surface to the second incident surface. The reflecting surface is opposite to the emitting surface, and the plurality of first microstructures are formed on the reflecting surface and extend parallel to the first and second incident surface. A distribution density and relative size of the first microstructures progressively decrease along directions from a center of the reflecting surface toward the first and second incident surface, respectively. The present light guide device does not employ additional optical correcting elements and thus has a simple structure. A backlight module using the same light guide device is also provided.

Abstract: An exemplary light guide plate (500) includes: a light incident portion (51) for receiving a light; a light reflecting portion (52) for reflecting the light input through the light incident portion; and a light emitting portion (53) opposite to the light reflecting portion, for outputting the reflected light. The light incident portion includes a first diffractive optical element (512) located thereat. The first diffractive optical element includes a plurality of protrusions (512a) each having a curved surface, with the protrusions being arranged symmetrically opposite to each other across a central axis of symmetry of the first diffractive optical element. The light emitting portion may include a second diffractive optical element (532) located thereat. The second diffractive optical element includes a plurality of elongate protrusions, with the protrusions being arranged symmetrically opposite to each other across a central axis of symmetry of the second diffractive optical element.

Abstract: An image pick-up lens system from an object side to an image side includes an aperture stop (10), and a meniscus-shaped lens (20) having a concave surface on the object side and a convex surface on the image side. The lens has at least one aspheric surface and a diffraction grating provided on the convex surface thereof. The lens system satisfies the following condition: (1) 0.1<R2/R1<0.5, wherein, R1 is an absolute value of a radius of curvature of the concave surface of the lens, and R2 is an absolute value of a radius of curvature of the convex surface of the lens. Condition (1) governs a distribution of refracting power for the lens, in order to correct monochromatic aberrations. The lens system also satisfies other conditions (2)-(4) as disclosed, in order to provide compactness, cost-effectiveness and improved optical performance.

Abstract: A light guide device includes a main body and a plurality of parallel elongate first V-shaped microstructures. The main body has an incident surface; an emitting surface adjoining the incident surface; and a reflecting surface opposite to the emitting surface. The first V-shaped microstructures are provided on the reflecting surface. Each of the first V-shaped microstructures has a triangular cross-section having a first base angle nearest the incident surface, a second base angle furthest from the incident surface and a vertex angle. A pitch between adjacent microstructures is configured to be substantially constant. A size of each of the first V-shaped microstructures is defined by the equation is y=9.2637×10?6x2?0.0003x+0.0232, wherein x is a distance from a given first V-shaped microstructures to the incident surface (in units of micrometers), and wherein y is a base width of the given first V-shaped microstructures (in units of micrometers).

Abstract: A light guiding plate (120) includes a light incident surface (121), a light emitting surface (122) adjacent to the light incident surface, and a bottom surface (123) opposite to the light emitting surface. The light incident surface includes at least one row of first grooves (1211) and at least one row of second grooves (1212). The first grooves is configured for increasing a range of incident angles in which light beams enter the light guiding plate via the light incident surface and thereby improving a brightness of the light guiding plate, and the second grooves is configured for complementing the functions of the first grooves thereby improving a uniformity of light output by the light guiding plate.

Abstract: An image pick-up lens system includes an aperture stop (10), a biconvex first lens (20), and a meniscus-shaped second lens (30) having a concave surface on a side of an object. The aperture stop, the first lens and the second lens are aligned in that order from the object side to an image side. Each of the lenses has at least one aspheric surface, and the following conditions are satisfied: (1) 0.5<f1/f<0.9, and (2) 1<T/f<1.62, wherein f1 is a focal length of the first lens, f is a focal length of the system, and T is a length from the aperture stop to an image pick-up surface of the image side.

Abstract: A backlight module includes a light guide plate, a light source, and a reflector. The light guide plate includes an incident surface and a corner adjacent the incident surface. The light source is disposed adjacent the incident surface and the corner of the light guide plate. The light source has an emitting surface. The reflector is disposed substantially facing the incident surface. The reflector has a curved reflective surface facing the emitting surface, the surface being shaped and positioned for uniformly reflecting light beams emitted from the light source into the light guide plate through the incident surface. An angle of inclination of the emitting surface with respect to the incident surface is chosen to be in the range from above about 0 to about 180 degrees. The backlight module can effectively eliminate shadow formation adjacent the incident surface of the light guide plate.

Abstract: A light guide plate includes an incident surface, an emission surface, and a bottom surface. The emission surface intersects with the incident surface and is substantially perpendicular to the incident surface. The bottom surface intersects with the incident surface and is opposite to the emission surface. The light guide plate further includes at least one light diffusing portion protruding from the incident surface. The light diffusing portion has a reflective hole located at (i.e., extending from) the bottom surface, the reflective hole protruding less than a thickness of the light guide plate. A backlight module, adopting the above-described light guide plate, further includes at least one corresponding light source positioned beside the incident surface of the light guide plate. The light source includes a luminescent surface facing a corresponding light diffusing portion of the light guide plate.

Abstract: A system for designing a free form reflector includes a user input interface (1), a free form reflector design unit (2), and a free form reflector output unit (3). The user input interface is configured for receiving various data associated with a desired free form reflector, via an input device. The free form reflector design unit is installed in a computer and configured for generating an optimum free form surface according to the input data by performing a non-uniform rational basis splines (NURBS) algorithm, a merit evaluation function, and a differential evolution (DE) algorithm. The free form reflector output module is configured for generating a free form reflector according to the optimum free form surface and outputting the free form reflector, in the form of a computer-aided design (CAD) drawing, to a display and/or a printer. A related method is also disclosed.

Abstract: A light guiding plate (120) includes a light incident surface (121), a light emitting surface (122) adjacent to the light incident surface, and a bottom surface (123) opposite to the light emitting surface. The light incident surface includes at least one row of first grooves (1211) and at least one row of second grooves (1212). The first grooves is configured for increasing a range of incident angles in which light beams enter the light guiding plate via the light incident surface and thereby improving a brightness of the light guiding plate, and the second grooves is configured for complementing the functions of the first grooves thereby improving a uniformity of light output by the light guiding plate.

Abstract: An image pick-up lens system includes an aperture stop (10), a biconvex first lens (20), a second lens (30) having a concave surface on an object side, and a third lens (40) having a concave surface on an image side. The aperture stop (10), the first lens (20), the second lens (30) and the third lens (40) are aligned in that order from the object side to the image side. All lenses in the system are made from a plastic or resin material, and one of them has a diffraction grating formed on a surface. The system satisfies conditions (1)-(5) as disclosed, in order to provide compactness, cost-effectiveness and improved optical performance.

Abstract: An image pick-up lens system includes an aperture stop (10), a biconvex first lens (20), and a meniscus-shaped second lens (30) having a concave surface on a side of an object. The aperture stop, the first lens and the second lens are aligned in that order from the object side to an image side. Each of the lenses has at least one aspheric surface, and both lenses are made from a same plastic or a resin. The system satisfies the following condition: (1) 1<T/f<1.7, wherein f is a focal length of the system, and T is a length from the aperture stop to an image pick-up surface of the image side. The first condition (1) limits the total length of the system in order to provide compactness. The system also satisfies other conditions (2)–(5) as disclosed, in order to provide compactness and cost-effectiveness and to correct fundamental aberrations.

Abstract: An image pick-up lens system includes an aperture stop (10), a first lens (20), and a second lens (30) having a concave surface on an object side. The aperture stop, the first lens and the second lens are aligned in that order from the object side to an image side. The first lens has positive refracting power and has a diffraction grating formed on a convex surface on the image side. The second lens has positive refracting power. The system satisfies the following condition: (1) 1.4<T/f<1.7, wherein f is a focal length of the system, and T is a length from the aperture stop to an image pick-up surface (50) of the image side. Condition (1) limits the total length of the system in order to provide compactness. The system also satisfies other conditions (2)–(5) as disclosed, in order to provide compactness, cost-effectiveness and improved optical performance.