158results about How to "Reduce spherical aberration" patented technology

An imaging lens assembly 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, a fifth lens element and a sixth lens element. The first lens element with negative refractive power has a convex object-side surface and a concave image-side surface. The second lens element has positive refractive power. The third lens element has refractive power. The fourth lens element with refractive power has an object-side surface and an image-side surface being aspheric. The fifth lens element with positive refractive power has an object-side surface and an image-side surface being aspheric. The sixth lens element with negative refractive power has a concave image-side surface, wherein at least one reflection point is formed on the image-side surface thereof.

The stereoscopic microscope includes a common close-up optical system that faces an object, a pair of zoom optical systems that form a pair of primary image, a pair of field stops, a pair of relay optical systems that relay the primary images to form a pair of secondary images, an inter-axis distance reducing element, an image taking device and an illuminating optical system. The object light rays incident on the close-up optical system form the primary images having predetermined parallax at the field stops through the zoom optical systems. The inter-axis distance reducing element reduces the inter-axis distance of the right and left light rays. The primary images are re-imaged by the relay optical systems as the secondary images on the adjacent regions on the single image taking surface of the image taking device, respectively.

The illumination source has a LED light source (2) generating a first divergent light field (6). The light from the LED light source (2) is processed by a first optical element (10), in particular a first lens element, to generate a second divergent light field (19). The first divergent light field (19) is processed by a second optical element (20) having a variable lens variable focus in order to generate a third light field (35) whose divergence can be varied.

Multifocal and single focus lenses are defined by nonconical aspheric optical surfaces. Various alternative surface shapes provide one or more vision regions bounded by optical steps. Each optical step has rapidly and smoothly changing power in the radial direction which creates an induced aperture through which the cortical elements of the human vision system are induced to concentrate. The induced aperture results in increased clarity and enhanced vision. In various configurations, the induced aperture decreases spherical aberration to further enhance vision. To increase correction intensity at one or more powers, redundant power regions are provided in repeated optical steps or annular apertures. In several embodiments, the redundant power regions create multiple induced apertures at one or more optical powers directed at one or more vision distances.

A symmetric relay system for endoscopes includes an optically-aligned pair of elongated concavo-convex rod-type lenses formed from crown glass, to the convex end surface of each of which a meniscus-shaped flint lens is cemented. The concave ends of the rod lenses are disposed to face the intermediate images of the relay system, and the convex ends to face the aperture of the relay system. A pair of achromatic lenses, each formed of a pair of lens elements x, y, are disposed adjacent and in optical alignment with the respective concave ends of the rod lenses between the concave rod ends and the intermediate images. Each achromatic lens fulfills the condition n x/ny=vx/vy. Apochromatic glass combinations may be used in the rod lenses to significantly reduce the secondary spectrum.

An imaging lens assembly includes six lens elements which are, 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, a fifth lens element and a sixth lens element. The second lens element has positive refractive power. The third lens element with negative refractive power has an image-side surface being concave in a paraxial region thereof. The fifth lens element with negative refractive power has an image-side surface being concave in a paraxial region thereof. The image-side surface of the fifth lens element has at least one inflection point.

Disclosed are an optical scanning system and an image forming apparatus having the same, wherein the optical scanning system includes a light source, a deflector, an input optical system for directing a light beam from the light source to the deflector, and an imaging optical system for directing the light beam deflected by the deflector onto a surface to be scanned, wherein the input optical system includes a first optical element having a power both in a main-scan sectional plane and in a sub-scan sectional plane, and a second optical element having a power in the sub-scan sectional plane, and wherein at least one surface of the first optical element has a shape being rotationally asymmetrical and, in the sub-scan sectional plane, being non-arcuate.

Optical systems (1-19) for endoscopes and the like are characterized by an integrated design in which the locations of the components and the aberration corrections are no longer tied to the optical functions of the objective (1-6) and the relays (7-19), and in which the relays may depart from symmetry. The power requirements can thus be shifted from one group to another, thereby reducing the overall power requirement. Moreover, the aberration correction can be shared between the optical group of the integrated system.

The invention relates to a lens which comprises a lens barrel, a first lens unit and a second lens unit are arranged in the lens barrel, a driving part is arranged on the first lens unit, and during zooming or focusing, the driving part shrinks or expands under the action of temperature so as to drive the first lens unit to move in the direction of an optical axis; and the second lens unit comprises a liquid lens, the liquid lens is filled with a transparent solution, and the transparent solution is heated to expand during zooming or focusing or is cooled to contract during zooming or focusingso as to regulate and control the focal power of the liquid lens. According to the lens, the use of a motor rotor and an induction coil can be avoided, and the thickness of the lens module is effectively reduced. The invention also relates to an image capturing device and electronic equipment.

An ellipsometer capable of generating a small beam spot is disclosed. The ellipsometer includes a light source for generating a narrow bandwidth probe beam. An analyzer is provided for determining the change in polarization state of the probe beam after interaction with the sample. A lens is provided having a numerical aperture and focal length sufficient to focus the beam to a diameter of less than 20 microns on the sample surface. The lens is formed from a graded index glass wherein the index of refraction varies along its optical axis. The lens is held in a relatively stress free mount to reduce stress birefringence created in the lens due to changes in ambient temperature. The ellipsometer is capable of measuring features on semiconductors having a dimensions as small as 50×50 microns.

With a high-density optical disc drive, although it is necessary to correct spherical aberrations which depend on a disc substrate thickness error, operation of an aberrations correction element takes time and therefore easy correction according to a disc radius degrades the operability of the apparatus.

The present invention comprises an optical pickup unit including an objective lens and an aberrations correction lens, a focus actuator, a tracking actuator, a aberrations correction motor, a seek motor, an aberrations correction lens control module, a radius information detecting module, and a system control module.

This disclosure provides an image capturing lens system, in order from an object side to an image side comprising: a first lens element with positive refractive power having a convex object-side surface and a concave image-side surface; a second lens element with positive refractive power; a third lens element with positive refractive power; and a fourth lens element with positive refractive power having a convex object-side surface, a concave at a paraxial region and convex at a peripheral region image-side surface, and both of the object-side and image-side surfaces thereof being aspheric. By arranging the four lens elements with refractive power, the refractive power can be applied on the four lens elements in a uniform manner, so as to reduce the sensitivity of the radius of curvature, and the thickness of the center or the like to produce an aberrance to improve the qualified rate of the production.

An optical lens system with a wide field of view includes, in order from the object side to the image side: a stop, a first lens element with a positive refractive power, a second lens element with a negative refractive power, a third lens element with a positive refractive power, and a fourth lens element with a negative refractive power. The focal length of the first lens element is f1, the focal length of the second lens element and the third lens element combined is f23, and they satisfy the relation: 0.4<f1/f23<1.7. When the above relation is satisfied, a wide field of view can be obtained and the resolution can be improved evidently.

The invention belongs to the technical field of microimaging, in particular to a lighting path of a plate lighting microscope and provides a lighting system of a plate lighting microscope with variable thickness and length of a plate. The system successively comprises a laser light source, a four-component mechanical compensation afocal zooming beam expanding system of a full spherical mirror, a cylindrical lens and a microobjective arranged along the optical axis from the object side to the image side; light emitted by the laser light source changes in aperture of a laser beam by means of theafocal zooming beam expanding system and then passes through the cylindrical lens rotating at 90 degrees by taking the optical axis as the rotating axis to form the plate light. The plate light undergoes subduction of spherical aberration generated by the afocal zooming beam expanding system and the cylindrical lens through a spherical aberration subduction microobjective, and the light intensityof the whole plate is more uniform; the plate lighting microscope can be used for observing biological samples in a certain dimensional range under the circumstance of not replacing the plate lighting system.

An image pickup lens comprises a first lens (L1) having a positive refractive power, an aperture stop (s3), a second lens (L2) having a negative refractive power and having a concave surface facing the image side, a third lens (L3) having a positive refractive power, and a fourth lens (L4) having a negative refractive power and having a concave surface facing the image side. The image pickup lens satisfies predetermined formulae.

The invention relates to a large visual field optical imaging method for guided missile detection and identification and a system thereof. The optical system is carried by a guided missile and used for target detection and identification, and comprises an optical glass ball cover, two folded plane reflectors, a band-pass filter, an electrical control diaphragm and an improved Pittsburgh Wan structural objective lens, wherein the improved Pittsburgh Wan structural objective lens is formed by two doublet lens groups and a meniscus lens. According to the invention, the two folded plane reflectors are adopted by the system, so that the system length is reduced, the mounting and adjustment are easy, and the stability is excellent; the requirement for the guided missile pre-reserved space is met while the veiling glare coefficient can be effectively reduced; the system is operated within a wide wave band range and a wide temperature range, chromatic aberration and optical aberration relevant to a visual field are reduced through selecting reasonable glass materials; the system adopts a refraction and reflection type optical structure, is simple and compact, is applicable to wider near-infrared band, has an adaptive temperature range, and has the characteristics of small chromatic aberration, strong athermalization capability, small distortion, excellent imaging performance and the like.