353results about How to "Correct chromatic aberration" patented technology

A folded lens system may include multiple lenses with refractive power and a light path folding element. Light entering the camera through lens(es) on a first optical path or axis is refracted to the folding element, which changes direction of the light onto a second optical path or axis with lens(es) that refract the light to form an image plane at a photosensor. At least one of the object side and image side surfaces of at least one of the lens elements may be aspheric. Total track length (TTL) of the lens system may be 16.0 mm or less. The lens system may be configured so that the telephoto ration |TTL/f| is greater than 1.0. Materials, radii of curvature, shapes, sizes, spacing, and aspheric coefficients of the optical elements may be selected to achieve quality optical performance and high image resolution in a small form factor camera.

An imaging system and method are presented. The system comprises an imaging lens unit, an imaging detector, and a birefringent element located between the imaging lens unit and the imaging detector. The system is thus configure and operable to provide in-focus imaging of objects located at both near-field and far-field ranges. Also provided is an optical device configured to be mounted on an imaging lens, being one of the following: a lens of an individual's glasses, on a contact lens, and an eye internal lens. The optical device is configured to be located between the imaging lens and the retina and comprises a birefringent element, to thereby provide in-focus imaging onto the retina of the objects located at both near-field and far-field ranges therefrom.

A method of and a device for the endoscopic fluorescence diagnosis of tissue, wherein the tissue is exposed to stimulating light via an endoscope for stimulation of fluorescence, which stimulating light is suitable, on account of its spectral distribution, to stimulate at least two different fluorescence modes in the tissue without filter switching in the stimulation beam path, and wherein the fluorescence light of the different fluorescence modes can be selectively observed.

An image recording and reproducing apparatus, an image pickup apparatus, and a chromatic aberration correcting method capable of performing excellent correction processing of an aperture amount of an iris and a lens image height of an object in an image pickup lens are provided.

An output signal from a camera signal processing circuit 4 is selected by a switch 5 to be supplied to a chromatic aberration correction unit 6. An aperture amount of an iris 31 provided in an image pickup lens 1 and coordinates of a pixel, to which correction processing is performed, from the chromatic aberration correction unit 6 are supplied to a conversion ratio calculation unit 10. A driving state such as a zoom focal length and focal position of the image pickup lens 1 and a camera shake correction vector are supplied to the conversion ratio calculation unit 10. Then, a conversion ratio for each color is obtained to be supplied to the chromatic aberration correction unit 6. Further, a signal corrected in the chromatic aberration correction unit 6 is compressed in a data compression circuit 15 to be supplied to a recording medium in a recording and reproducing apparatus 17. A signal reproduced from the recording and reproducing apparatus 17 is decompressed in a data decompression circuit 18 to be supplied to the switch 5. Accordingly, picture-quality degradation occurring in a miniaturized image pickup lens can be corrected by processing a picked-up image signal, and excellent correction processing can be performed on an aperture amount of an iris and a lens image height of an object in the image pickup lens.

The present invention provides a wide-angle imaging lens assembly comprising, in order from an object side to an image side: a first lens element with negative refractive power having a convex object-side surface and a concave image-side surface; a second lens element with negative refractive power having a convex object-side surface and a concave image-side surface; a third lens element with positive refractive power; a fourth lens element with negative refractive power having a concave image-side surface; and a fifth lens element with positive refractive power; wherein the two lens elements with refractive power closest to the object side are the first lens element and the second lens element; and wherein the number of lens elements with refractive power does not exceed six.

An imaging lens includes a first lens group having positive refractive power; a second lens group having positive refractive power; and a third lens group having negative refractive power, arranged in this order from an object side to an image plane side. The first lens group includes a first lens having positive refractive power, a second lens having negative refractive power, and a third lens having positive refractive power. The second lens group includes a fourth lens having positive refractive power and a fifth lens having positive refractive power. The third lens group includes a sixth lens and a seventh lens. The first to fifth lenses have specific Abbe's numbers.

An optical pickup apparatus for conducting recording and/or reproducing information of an optical information recording medium, comprises a light source; a converging optical system having an objective lens; and a photo-detector. The converging optical system comprises a plastic lens and a spherical aberration deviation correcting element to correct deviation of a spherical aberration of the converging optical system. A numerical aperture of the objective lens at an image-side is 0.65 or more.

This invention provides an optical photographing system comprising four lens elements with refractive power, in order from an object side to an image side: a first lens element; a second lens element with positive refractive power, and at least one of the object-side and image-side surfaces thereof being aspheric; a third lens element with negative refractive power having a concave object-side surface and a convex image-side surface, and both of the object-side and image-side surfaces thereof being aspheric; a fourth lens element with positive refractive power, and both of the object-side and image-side surfaces thereof being aspheric; wherein the optical photographing system further comprises an aperture stop positioned between an object and the second lens element. By such arrangement, total track length of the optical photographing system can be effectively reduced. Wide view-angle and high image resolution are also obtained.

An image capturing lens system includes, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power; a third lens element having an object-side surface and an image-side surface which are both aspheric; a fourth lens element with negative refractive power having an object-side surface and an image-side surface which are both aspheric; a fifth lens element having an object-side surface and an image-side surface which are both aspheric; and a sixth lens element having a concave object-side surface and a convex image-side surface which are both aspheric. With such arrangements, the convergent capability is mainly contributed from the object side of the lens assembly for higher portability of the lens system. Additionally, the peripheral image curve can be prevented while correcting the chromatic aberration and the peripheral image focus.

In a projection optical system which forms an image of a first plane on a second plane, using extreme ultraviolet illumination light, an object of the invention is to form an image on the first plane on the second plane under suitable conditions. This projection optical system comprises a first diffractive optical element arranged in an optical path between the first plane and the second plane; a second diffractive optical element arranged in the optical path on the side of the second plane from the first diffractive optical element; and an optical system having a negative power, arranged in the optical path between the first diffractive optical element and the second diffractive optical element.

This invention provides an image-capturing lens assembly comprising, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface; a second lens element with negative refractive power; a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, the object-side and image-side surfaces thereof being aspheric; a fourth lens element with negative refractive power having a concave image-side surface on which at least one inflection point is formed, the object-side and image-side surfaces thereof being aspheric; and a stop disposed between an imaged object and the first lens element; wherein there are four lens elements with refractive power. Such an arrangement of optical elements can effectively reduce the size of the lens assembly, mitigate the sensitivity of the optical system and enable the lens assembly to obtain a higher resolution.

The invention discloses a photographic system, an image pickup device and an electronic device. The photographic system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens which are distributed from an object side to an image side sequentially; the first lens has positive refractive power, and the object side surface of the first lens is a convex surface near an optic axis; the second lens has refractive power, and the image side surface of the second lens is a concave surface near the optical axis; each of the third lens, the fourth lens and the fifth lens has refractive power; the sixth lens has refractive power, the image side surface of the sixth lens is a concave surface near the optical axis, the image side surface of the sixth lens is provided with at least one convex surface at an off-axis, and the image side surface and object side surface of the sixth lens are both an aspheric surface; the seventh lens has refractive power, the object side surface of the seventh lens is a concave surface near the optic axis, and the image side surface and object side surface of the seventh lens are both an aspheric surface; no relative movement occurs among the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens on the optical axis; and an air gap is left between any two adjacent lenses of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens on the optical axis. The invention also discloses a photographic system with the above image pickup device and an electronic device with the image pickup device.

This invention provides an optical imaging lens assembly, in order from an object side toward an image side including: a first lens element with positive refractive power having a convex object-side surface, a second lens element with negative refractive power having a concave object-side surface and a concave image-side surface, a third lens element with positive refractive power having a concave object-side surface and a convex image-side surface, a fourth lens element with negative refractive power having a concave image-side surface, and the two surfaces being aspheric; wherein the optical imaging lens assembly further comprises an aperture stop disposed between an imaged object and the first lens element, and there are four lens elements with refractive power.