Abstract: A zoom lens includes, from the object side, a positionally-fixed first lens group having a positive refracting power, a second lens group having a negative refracting power and movable in an optical axis direction for zooming, a third lens group having a positive refracting power, and a fourth lens group movable in the optical axis direction. The first lens group includes a negative lens, a positive lens and another positive lens disposed in order from the object side and satisfies 15.0<ft/fw<31.0??(1) 7.0<f1/fw<13.0??(2) ?8.5<fL1/fw<?4.0??(3) where fw and ft are the focal lengths of the entire lens system in a wide angle end state and a telephoto end state, respectively, f1 is the focal length of the first lens group, and fL1 is the focal length of the negative lens of the first lens group.

Abstract: The diameter of an endoscope insertion portion is reduced, and a wide field angle of an endoscope insertion portion is obtained. An endoscope objective optical system includes, from an object side, a first lens formed of a plano-concave lens having a concave surface facing an image side, a second lens formed of a plano-concave lens having a concave surface facing the object side, an aperture stop, and a third lens formed of a plano-convex lens having a plane surface facing the object side, and satisfies 0.7?|fab/f|0.9 1.7?|fe/fab|?2 2?fb/fa?4 where f: focal length of the entire system; fa: focal length of the first lens; fb: focal length of the second lens; fe: represents focal length of the third lens; fab: combined focal length from the first lens to the second lens.

Abstract: Embodiments of the invention provide apparatuses and methods for phase correlated seeding of parametric mixer and for generating coherent frequency combs. The parametric mixer may use two phase-correlated optical waves with different carrier frequencies to generate new optical waves centered at frequencies differing from the input waves, while retaining the input wave coherent properties. In the case when parametric mixer is used to generate frequency combs with small frequency pitch, the phase correlation of the input (seed) waves can be achieved by electro-optical modulator and a single master laser. In the case when frequency comb possessing a frequency pitch that is larger than frequency modulation that can be affected by electro-optic modulator, the phase correlation of the input (seed) waves is achieved by combined use of an electro-optical modulator and injection locking to a single or multiple slave lasers.

Abstract: There is provided an image pickup lens having a 6-element structure which has a small size and a sufficiently lens speed of F/2 or less and in which various aberrations are corrected favorably.

Abstract: An imaging lens including: in order from an object side thereof, a first lens having a positive refractive power; a second lens formed in a meniscus shape having a negative refractive power with a concave surface faced to an image side; a third lens formed in a biconvex shape having a positive refractive power near an optical axis; a fourth lens formed in a meniscus shape having a positive refractive power with a concave surface faced to the object side near the optical axis; and a fifth lens having a negative refractive power near the optical axis and a positive refractive power in a peripheral portion, the imaging lens satisfying the following conditional expression (a), 3.0?f3/f4?30.0 (a) where f3 is a focal length of the third lens, and f4 is a focal length of the fourth lens.

Abstract: An interface between two different optical materials can comprise a stack of thin film layers that manage light incident on that interface. One of the optical materials can have a first composition and a first refractive index, while the other optical material can have a second composition and a second refractive index. The stack can comprise thin film layers of the first optical material interleaved between thin film layers of the second optical material. The layers of the stack can be configured to provide the stack with an aggregate composition of at least one of the optical materials that progressively varies from one end of the stack to the other end. To provide the progressive variation in composition, the layers of one of the optical materials can have a progressively increased thickness across the stack, or can progressively increase in number, for example.

Abstract: An imaging lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has positive refractive power. The third lens element has positive refractive power. The fourth lens element has refractive power. The fifth lens element with refractive power has a concave image-side surface at a paraxial region, and the image-side surface thereof changes from concave at the paraxial region to convex at a peripheral region, wherein both of an object-side surface and the image-side surface are aspheric.

Abstract: Disclosed herein is a zoom lens, including: a first lens group having a positive refracting power; a second lens group having a negative refracting power; a third lens group having a positive refracting power; and a fourth lens group having a positive refracting power; the first, second, third and fourth lens groups being disposed in order from the object side; the lens groups moving upon zooming from a wide angle end to a telephoto end of the zoom lens such that the distance between the first lens group and the second lens group increases while the distance between the second lens group and the third lens group decreases.

Abstract: A light modulator pixel unit and a method for manufacturing the same are provided. The light modulator pixel unit includes top, movable and bottom electrodes. Under control of a control circuit, the movable electrode may shift to first, second and third positions corresponding to modulations of first, second and third monochromatic lights, respectively. When the movable electrode is at a certain position, the incident light corresponding to the position may be divided into two parts, one is reflected by the top electrode, and the other one may bypass the top electrode and be reflected by the movable electrode. The two parts may interfere destructively. The light modulator pixel unit of the present invention can control monochromatic lights of three special wavelengths by time division, and enable color control and gray control. The unit is applicable in the field of projection display and panel system.

Abstract: There is provided a lens module, including: a first lens having positive refractive power, an object-sided surface thereof being convex; a second lens having negative refractive power, an image-sided surface thereof being concave; a third lens having positive refractive power; a fourth lens having negative refractive power, an image-sided surface thereof being convex; and a fifth lens having negative refractive power, an image-sided surface thereof being concave, wherein the fourth lens satisfies Conditional Expression 1, f ? ? 4 f < - 3.0 [ Conditional ? ? Expression ? ? 1 ] where f is an overall focal distance of an optical system and f4 is a focal distance of the fourth lens.

Abstract: There is provided a lens module, including: a first lens having positive refractive power, an object-sided surface thereof being convex; a second lens having negative refractive power, an image-sided surface thereof being concave; a third lens having positive refractive power; a fourth lens having negative refractive power, an image-sided surface thereof being convex; and a fifth lens having negative refractive power, an image-sided surface thereof being concave, wherein the fourth lens satisfies Conditional Expression 1, f ? ? 4 f < - 3.0 [ Conditional ? ? Expression ? ? 1 ] where f is an overall focal distance of an optical system and f4 is a focal distance of the fourth lens.

Abstract: A lens optical system includes first, second, third, and fourth lenses that are arranged between an object and an image sensor, in order from an object side, wherein the first lens has positive refractive power and an incident surface that is convex toward the object, the second lens has negative refractive power and both surfaces of which are concave, the third lens has positive refractive power and a meniscus shape that is convex toward the image sensor, and the fourth lens has negative refractive power and at least one of an incident surface and an exit surface of which is an aspherical surface, wherein the system satisfies the inequality, 3.0<TTL/BL<3.4, wherein TTL is a distance from the incident surface of the first lens to the image sensor and BL is a distance from the exit surface of the fourth lens to the image sensor.

Abstract: There is provided a lens module, including: a first lens having positive refractive power, an object-sided surface thereof being convex; a second lens having negative refractive power, an image-sided surface thereof being concave; a third lens having positive refractive power; a fourth lens having negative refractive power, an image-sided surface thereof being convex; and a fifth lens having negative refractive power, an image-sided surface thereof being concave, wherein the fourth lens satisfies Conditional Expression 1, f ? ? 4 f < - 3.0 [ Conditional ? ? Expression ? ? 1 ] where f is an overall focal distance of an optical system and f4 is a focal distance of the fourth lens.

Abstract: An optical system includes, in order from an object side to an image side, a front unit having a positive refractive power, an aperture diaphragm, and a rear unit. The front unit includes a first lens unit having a positive refractive power. The rear unit includes a second unit adjacent to the aperture diaphragm and configured to move in focusing. The first lens unit includes n (which is an integer of 2 or higher) positive lenses and one or more negative lenses. The materials of at least two positive lenses of the n positive lenses in the first lens unit satisfy 0.0100<??gF where ??gF is an abnormal partial dispersion of each material. The material of one or more positive lenses of the n positive lenses in the first lens unit satisfies 0.0272<??gF. Additional conditional expressions are satisfied.

Abstract: A device comprises at least one optics member (O) comprising at least one transparent portion (t) and at least one blocking portion (b). The at least one transparent portion (t) is made of one or more materials substantially transparent for light of at least a specific spectral range, referred to as transparent materials, and the at least one blocking portion (b) is made of one or more materials substantially non-transparent for light of the specific spectral range, referred to as non-transparent materials. The transparent portion (t) comprises at least one passive optical component (L). The at least one passive optical component (L) comprises a transparent element (6) having two opposing approximately flat surfaces substantially perpendicular to a vertical direction in a distance approximately equal to a thickness of the at least one blocking portion (b) measured along the vertical direction, and, attached to the transparent element (6), at least one optical structure (5).

Abstract: Provided is an objective optical system comprising, in order from an object side: an aperture stop; a positive first group; a second group; a positive third group; and a fourth group, wherein the first group is formed of a single meniscus lens or plano-convex lens, whose convex surface faces an image side, the second group is formed of a single lens, the third group is formed of a cemented lens consisting of a positive lens and a negative lens, the fourth group is formed of a single lens, and Conditional Expressions (7) and (8) below are satisfied, where f is a focal length of an entire system, f4 is a focal length of the fourth group, and f2 is a focal length of the second group. ?0.5<f/f4<?0.001??(7) 0.1?|f4/f2|?5.

Abstract: An imaging lens substantially consists of five lenses of an aspheric first lens having a convex surface facing an object side and positive refractive power, an aspheric second lens having a concave surface facing the object side and negative refractive power, an aspheric third lens having a meniscus shape in which its object-side surface is convex toward the object side, and positive refractive power, an aspheric fourth lens having negative refractive power and a fifth lens having a convex surface facing the object side and positive refractive power, which are in this order from the object side. Further, the imaging lens satisfies predetermined conditional formulas.

Abstract: The thermally switched absorptive optical shutter may be a self-regulating “switchable absorber” device that may absorb approximately 100% of incoming light above a threshold temperature, and may absorb approximately 50% of incoming light below a threshold temperature. The shutter may be formed by placing a thermotropic depolarizes between two absorptive polarizers. This control over the flow of radiant energy may occur independently of the thermal conductivity or insulation of the shutter device and may or may not preserve the image and color properties of incoming visible light. This has energy-efficiency implications as it can be used to regulate the internal temperature and illumination of buildings, vehicles, and other structures without the need for an external power supply or operator signals. The shutter device has unique optical properties that are not found in traditional windows, skylights, stained glass, light fixtures, glass blocks, bricks, or other building materials.

Abstract: An image pickup lens includes a controller and a manipulator position detector configured to detect a position of a manipulator configured to accept a manipulation used to move the lens. When the manipulation of the manipulator becomes valid and a difference between the position of the manipulator when the manipulation of the manipulator is invalid and the position of the manipulator when the manipulation of the manipulator is valid is equal or smaller than a threshold, the controller controls a movement of the lens from an initial position that is the position of the lens when the manipulation of the manipulator is invalid. When the manipulation of the manipulator becomes valid and the difference is larger than the threshold, the controller controls a movement of the lens from an initial position that is the position of the lens corresponding to the manipulator's position detected by the manipulator position detector.

Abstract: The thermally switched reflective optical shutter is a self-regulating “switchable mirror” device that reflects up to 100% of incident radiant energy above a threshold temperature, and reflects up to 50% of incident radiant energy below a threshold temperature. Control over the flow of radiant energy occurs independently of the thermal conductivity or insulating value of the device, and may or may not preserve the image and color properties of incoming visible light. The device can be used as a construction material to efficiently regulate the internal temperature and illumination of buildings, vehicles, and other structures without the need for an external power supply or operator signals. The device can be tailored to transmit sufficient visible light to see through in both the transparent and reflective states, while still providing significant control over the total energy transmission across the device.