234results about How to "Shorten focal length" patented technology

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. This image pickup lens includes a first lens having a positive refractive power and comprising a convex surface directed to the object side; a second lens having a negative refractive power and comprising a concave surface directed to the image side; a third lens having a positive or negative refractive power; a fourth lens having a positive refractive power; a fifth lens having a positive refractive power and comprising a convex surface directed to the image side; and a sixth lens having a negative refractive power and comprising a concave surface directed to the image side, in this order from the object side, wherein the image side surface of the sixth lens has an aspherical shape and an inflection point at a position other than an intersection point with the optical axis, and the image pickup lens satisfies the following conditional expressions.

ν1>50

ν2≦30

where,

• • ν1 is an Abbe number of the first lens, and
  • ν2 is an Abbe number of the second lens.

An image display apparatus that presents an observer an image of higher resolution than the original resolution of an image display device used, thereby allowing the observer to view a clear and beautiful image. An illuminating optical system (5) illuminates an image display device with illuminating light from a light source (1). The image display device displays an image by transmission or reflection of the illuminating light. A viewing optical system leads the image to an observer's eyeball (10). The apparatus has two image display devices (9a and 9b). An optical coupling/separating element having a light-coupling or light-separating action is provided between the image display devices (9a and 9b) and the observer's eyeball (10) to superimpose images of the two image display devices on one another. The optical coupling/separating element has an optical coupling/separating surface (40) tilted at an angle of approximately 45 degrees with respect to each of the image display devices (9a and 9b). The viewing optical system projects the superimposed images into one eyeball (10) of the observer as an enlarged virtual image.

The invention relates to an eyepiece, in particular to an eyepiece used in a head-mounted display, belonging to the field of optical technique. The eyepiece is formed by six pieces of lenses, and a lens screen, the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens are sequentially arranged from the observing side of human eyes and the display device side along the direction of an optic axis in a coaxial way; the exit pupil diameter of the eyepiece is larger than that of the common eyepiece, the eye relief is long, the angle of view field is large, and the focal distance and F/# are small; furthermore, illuminance of image plane is evener, so that the eyepiece especially meets the requirements of the head-mounted display.

The planar lens of the invention having a flat glass substrate, in which a refractive index distribution is formed by diffusing a refractive index-increasing component into the flat glass substrate in a substantially hemispherical form or semicylinder form, wherein the refractive index-increasing component is silver, and the flat glass substrate comprises Li as an alkali metal that is subject to an ion exchange with the silver.

An optical lens assembly for image taking, sequentially arranged from an object side to an image side, comprising: the first lens element with positive refractive power having a convex object-side surface; the second lens element with negative refractive power having a convex object-side surfaces and a concave image-side surface; the third lens element with positive refractive power having a convex image-side surface; the fourth lens element with refractive power having two aspheric optical surfaces; the fifth lens element with refractive power having a concave object-side surface and both aspheric optical surfaces; an image sensor disposed on an image plane and a stop provided for imaging a photographed object; specific relations being satisfied. Thereby, the optical lens assembly for image taking has good aberration correction, and can shorten the total length for use in compact cameras and mobile phones requiring high resolution.

An image pick-up optical lens assembly, sequentially arranged from an object side to an image side along an optical axis, comprises: a first lens element with a positive refractive power having a convex object-side surface, a second lens element with a negative refractive power, a third lens element with a positive refractive power, a meniscus fourth lens element with a positive refractive power having at least one aspherical optical surface, and a fifth lens element with a positive refractive power having at least one inflection point on the optical image-side surface. Additionally, the image pick-up optical lens assembly satisfies several particular conditions. The invention possesses features such as good aberration compensation, well-performed modulation transfer function and short total length of lens assembly applicable for compact cameras and mobile phones.

Disclosed is a wide-angle lens having a viewing angle of more than 130°. The wide angle lens has a front group, an aperture, and a rear group arranged in this order from an object side to an image side. The front group has a first lens as a negative lens, a second lens as a negative lens, and a third lens as a positive lens arranged from the object side to the image side. The rear group is a cemented lens having a positive power when two lenses are bonded to each other. The wide-angle lens constitutes an image forming system with the five lenses as a whole, the first lens and the second lens of the front group are aspherical lenses, and the third lens is a spherical lens.

A method and system of image processing on a computer, and a computer program product adapted for image processing, wherein a digital image of an article is imported into a computer, the digital image is color-corrected, an internal palette is generated from a database of predetermined color attributes and applied to the color-corrected digital image so as to generate a second digital image, and wherein a third digital image corresponding to the second digital image is generated, but replacing the predetermined color attributes with vivid color attributes. The present invention is of particular utility in the manufacture of dental prostheses from ceramics materials which substantially match a person's natural tooth colors.

A technology is provided in which a contaminant on a condenser lens in a laser processing machine is detected by detecting a change in focal lengths of the lens. A laser beam LB emitted from a laser resonator 10 is condensed by a condenser lens 100 in a processing head 50 to be irradiated from a nozzle 60 toward a test piece TP. A control device of the laser processing machine controls the moving of the processing head 50 in the Z axis direction and records the Z coordinate of the head. When a focal point falls on a surface of the test piece TP, a blue flame BF is generated. A light receiving device 300 receives the blue flame and sends a signal to the control device. In a contaminated condenser lens 100, a heat is accumlated, which expands the lens and reduces the focal length of the lens. A contaminant on the condenser lens is detected by using this change.

The invention discloses a spectrum beam combination device for realizing twice diffraction by using the transmission grating of a plated reflecting film. The spectrum beam combination device comprises a semiconductor laser unit light source, a slow-axis collimated column lens, a conversion lens, a transmission grating and an output coupling mirror. The transmission grating of the back plated reflecting film is used as a diffraction element, namely the reflecting film is plated at the back of a grating surface, so that the dispersive power of the grating can be doubled by an incident beam through the diffraction of the transmission grating twice. According to the spectrum beam combination device, the restriction that the dispersive power of the diffraction grating is limited in traditional spectrum beam combination is overcome, the number of beam combination elements can be increased in the gain line width of the material and the high-efficiency diffraction wavelength range of the grating, and the output power is obviously improved, or the length of a resonant cavity can be shortened when certain output spectrum width is guaranteed, so that the structure of a laser unit is compacter, and the mode of the laser unit is stabler.

A projector that displays a projection frame includes an operation unit to select a projection mode designating the number of split screens in the projection frame and the location, size, and orientation of each split screen. An input unit processes graphical signal data provided from an external graphical signal generator to generate processed graphical signal data. A distributor distributes the processed graphical signal data to graphical signal processing circuits, each performing data conversion and adjustment in accordance with the projection mode on the distributed graphical signal data to generate adjusted graphical signal data for one of the split screens. A synthesizer combines the adjusted graphical signal data to generate combined graphical signal data. A projection unit projects the combined graphical signal data as a single projection frame.

A first holding member holds a first optical system and a first mirror, and has a first junction surface. A second holding member holds a second optical system and a second mirror, and has a second junction surface. A junction portion is configured such that, in a state where the first junction surface and the second junction surface are aligned with each other, the second holding member is capable of being shifted in a direction of both the junction surfaces and rotated around an optical axis, and makes it possible to perform optical axis alignment. An emission-side optical axis of the first optical system and an incidence-side optical axis of the second optical system are aligned with each other, and thus a U-shaped optical path is formed by the first and second optical systems.

A liquid crystal composition include a first compound (a) and a second compound (b), wherein the molecular structure formula of the first compound is represented as follows and the molecular structure formula of the second compound is represented as follows. The liquid crystal composition also includes a third compound (c) of which the molecular structure formula is represented as follows. The liquid crystal composition has high birefringence. The invention also relates to a liquid crystal lens including the liquid crystal composition.

The invention relates to a zoom lens that enables an optical path to be easily bent by a reflecting optical element, has a wide-angle design and high optical performance as represented by a high zoom ratio of about 3.4, is extremely slimmed down in the depth direction, and costs less. The zoom lens comprises a positive first lens group G1, a negative second lens group G2, a positive third lens group G3, a positive fourth lens group G4 and a negative fifth lens group G5. Upon zooming from the wide-angle end to the telephoto end, the first lens group G1 remains substantially fixed with respect to an image plane I, and at least the second G2 and the fourth lens group G4 move. The first lens group G1 includes a reflecting optical element for bending the optical path involved, and a portion of the first lens group G1 on an object side with respect to the reflecting surface has negative refracting power. The zoom lens satisfies condition (1) with respect to the focal length of the fifth lens group G5.

Large aperture optical systems that are extremely well corrected over a large flat field and over a large spectral range are disclosed. Breathing and aberration variation during focusing are optionally controlled by moving at least two groups of lens elements independently. Aberration correction in general is aided by allowing the working distance to become short relative to the format diagonal. Field curvature is largely corrected by a steeply curved concave surface relatively close to the image plane. This allows the main collective elements to be made of low-index anomalous dispersion materials in order to correct secondary spectrum. In wide-angle example embodiments, distortion may be controlled with an aspheric surface near the front of the lens.

A multi-lens based capturing apparatus and method are provided. The capturing apparatus includes a lens array including lenses and a sensor including sensing pixels, wherein at least a portion of sensing pixels in the sensor may generate sensing information based on light entering through different lenses in the lens array, and light incident on each sensing pixel, among the portion of the plurality of sensing pixels may correspond to different combinations of viewpoints.

The invention relates to a solar energy strong-efficiency light condensing and sun facing device. A machine body shell is internally provided with a solar energy collector and a swivel condensing lens, wherein the upper side of the solar energy collector is provided with a rotating frame and the swivel condensing lens; the swivel condensing lens is fixedly arranged on a light condesnsing hood; a motor can drive the rotating frame to rotate at regular time to turn the solar energy collector towards a sun light source; the swivel condensing lens gathers multiple sun light energy onto the solar energy collector; the swivel condensing lens effectively shortens the distance between the condensing lens and the solar energy collector; the multiple sun light energy makes the solar energy collector emit multiple thermoelectrical energy; and the motor rotates the rotating frame at regular time to make the solar energy collector automatically rotate to chase the sun direction and face the sun so as to improve the efficiency of the solar energy generating power or collecting heat.

A photographic wide-angle lens system with internal focusing has a front array (II) of negative refractive power that is rigid within itself and fixed on the object-side, a rear array (III) of positive refractive power that is rigid within itself and fixed on the image side of an aperture diaphragm (A), and a focusing array (II) of positive refractive power having an optical single element (5) that is arranged between the front array (I) and the aperture diaphragm A and is axially movable from a maximum axial position on the object side to a maximum axial position on the image side to vary the focus distance from its maximum to its minimum value. The optical single element of the focusing array (II) has at least one aspheric surface (51, 52) and the image-side end lens (9) of the rear array (III) is configured as a positive, aspheric meniscus lens.