43results about How to "Sufficient optical performance" patented technology

There is a need for providing a projection optical system that is appropriate for maintaining high resolution with low distortion, miniaturizing a reflector, decreasing the number of reflectors, and decreasing the depth and the bottom (or top) of a display used for a rear projection television, for example. The projection optical system according to the invention enlarges and projects images from a primary image surface existing at a reducing side to a secondary image surface existing at an enlarging side. The projection optical system has a first optical system L11 and a second optical system L12. The first optical system L11 forms an intermediate image (position II) of the primary image surface. The second optical system L12 has a concave reflector AM1 that forms the secondary image surface resulting from the intermediate image. A light beam travels from the center of the primary image surface and to the center of the secondary image surface and crosses an optical axis. The light beam is reflected on the concave reflector, crosses the optical axis again, and reaches the secondary image surface.

A method for producing an optical element by bonding a plurality of optical member with an adhesive, which is capable of providing the optical element with sufficient optical performance and with such a sufficient bonding strength to prevent separation from being made at bonded portions, and of making alignment easily, is provided. The method for producing an optical element, which comprises bonding two or more optical members with an adhesive, is characterized in that at least one of confronting bonded surfaces on at least one pair of contact surfaces of the optical members is subjected to dry cleaning in such a state that at least a surface connecting to a bonded surface is masked, followed by applying a liquid adhesive as the adhesive on the cleaned surface and curing the liquid adhesive to bond the optical members.

An optical lens assembly includes a first lens of positive refractive power, a second lens of refractive power, at least one of the object surface and the image surface being aspherical, a fourth lens of refractive power, a fifth lens of a concave object surface near its optical-axis and both the object surface and the image surface being aspherical so that the Abbe number υ4 of the fourth lens, the Abbe number υ5 of the fifth lens, an air gap G₁₂ between the first lens and the second lens, an air gap G₂₃ between the second lens and the third lens, an air gap G₄₅ between the fourth lens and the fifth lens, the second thickness T₂ of the second lens, the third thickness T₃ of the third lens, the fourth thickness T₄ of the fourth lens, and the fifth thickness T₅ of the fifth lens satisfy 18≦υ4−υ5≦50 and (G₁₂+T₂+G₂₃+T₃+T₄+G₄₅+T₅)/G₃₄≦6.3.

The invention provides an optical imaging lens, which comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens sequentially from the object side to the image side and satisfies the following relational expressions: 1<=EFL/TTL and TTL<=18mm. By controlling the arrangement of the concave and convex surfaces of the lenses and using at least one relational expression to control relevant parameters, the length of the optical imaging lens is shortened under the condition of maintaining good optical performance. The optical imaging lens of the invention is used in optical imaging.

An imaging optical system has, in order from the object side to the image side thereof, a front lens group, an aperture stop, and a rear lens group. A lens located closest to object side in said front lens group always remains fixed in position, with satisfaction of the following conditions (1) and (2):

1.15≦fb/IHω≦1.7   (1)

−4.0≦fn/f≦−1.3   (2)

where f is a focal length of the whole imaging optical system, fn is a focal length of a first negative lens in said front lens group, fb is a back focus of the imaging optical system upon focusing on an object point at infinity, and IHω is a distance from an optical axis of a position where a chief ray from a maximum incident half angle of view (ω) upon focusing on an object point at infinity is imaged at the imaging plane.

An imaging lens includes, in order from an object side, a first lens having a negative power and including a concave image-side surface, a second lens having a positive power, a stop, a third negative lens, which is a biconcave lens, a fourth lens having a positive power, and a fifth lens having a positive power and including a convex image-side surface. The imaging lens satisfies the following conditional expressions:

0.18<(D4+D5)/f<0.44, and

0.18<D1/f

where f denotes a focal length of an entire lens system, D1 denotes a thickness of a center of the first lens, D4 denotes a distance from an image-side surface of the second lens to the stop on an optical axis, and D5 denotes a distance from the stop to an object-side surface of the third lens on the optical axis.

The invention provides a portable electronic device and an optical imaging camera lens thereof. The optical imaging camera lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, and a fifth lens from the object side to the image side. The optical imaging camera lens only comprises the five lenses with the refractive index. ALT represents the thickness sum of the five lenses on the optical axis, G45 represents an air gap width between the fourth lens and the fifth lens on the optical axis, and ALT/G45 is no more than 6.0. The electronic device comprises a shell and an image module which is installed in the shell. The image module comprises the above mentioned optical imaging camera lens, a lens cone, a module backseat unit, a substrate, and an image sensor. The portable electronic device and the optical imaging camera lens thereof are used for optical photography. By controlling the arrangement of concave-convex curved surfaces of all the lenses, the length of the camera lens is reduced on the condition of maintaining the good optical property.

The invention relates to an optical lens group. The object side surface of a first lens comprises a convex part near a circumference. A second lens has the negative refraction rate. The object side surface of a third lens comprises a concave part near the circumference. The image side surface of a fourth lens comprises a convex part near the circumference. The optical lens group meets the following relation: HFOV <= 25 DEG.; TTL <= 8mm; and TL/G23 <=4.5, wherein HFOV represent a half visual angle of the optical lens group, TTL represents a distance from the object side surface of the first lens to an imaging surface on the optical axis, TL represents a distance from the object side surface of the first lens to the image side surface of the fifth lens on the optical axis, and G23 represent the width of an air gap between the second lens and the third lens on the optical axis. Through controlling the concave and convex arrangement of each lens, the lens length is shortened in the condition of maintaining good optical performance.

A protective optical filter assembly for thin film filters having two transparent substrates facing one another and separated by a resilient element, a sealed region is formed between the transparent substrates by applying a compressive force that compresses the resilient element. The thin film filter may be contained within a carrier. The compressive force may be generated by one or more interference-fit aperture rings or threaded apertures ring, a given aperture ring may be opposed by another such aperture ring or a fixed stop. Alternatively a snap fit carrier may be used to generate the compressive force. The sealed region may have a gas having a positive pressure or a liquid.

A lens tilt adjusting mechanism is configured by a piezoelectric element, a lens holder formed into a ring shape, and a holder fit-in part arranged in a tubular form in the movable part of an actuator. An objective lens is fixed on an inner side of the lens holder, the lens holder is fitted to the inner side of the holder fit-in part and held in the holder fit-in part in a tiltable manner when an outer peripheral surface contacts and slides along an inner peripheral surface of the holder fit-in part; the piezoelectric element is attached on the inner side of the holder fit-in part so that one end in an extending and contracting direction of the piezoelectric element contacts a step surface formed on the inner side of the holder fit-in part and the other end contacts the surface on the side away from an optical recording medium side of the lens holder; and other members are not interposed between the objective lens and the optical recording medium.

An optical lens assembly includes a first lens of a concave image surface near its periphery, a second lens of a plastic material, a third lens of a concave object surface near the optical-axis and a concave image surface near its periphery, a fourth lens of a concave object surface near the optical-axis, a fifth lens of a concave object surface near its periphery and a convex image surface near the optical-axis.

An optical lens set includes: a first, second, third, fourth and fifth lens element, an aperture stop disposed between said first and second lens element, said first lens element has negative refractive power, and has an object-side surface with a convex part in a vicinity of its periphery, said third lens element has an image-side surface with a concave part in a vicinity of its periphery, said fourth lens element has an object-side surface with a concave part in a vicinity of its periphery, said fifth element has aspherical object-side and image-side surfaces. T1, T2 and T5 are the thicknesses of said first, second and fifth lens element along the optical axis respectively, G12 and G23 are an air gaps between said first and second lens element, and between said second and third lens element along said optical axis respectively, the optical lens set satisfies the relationships: (G12+T2)/T1≤2.9 and (T1+T5+G23)/T2≤1.9.

A lens is equipped with a reference mounting surface that is abutted to a surface of a lens support member at the time of mounting the lens, wherein the reference mounting surface is arranged between a plane which is normal to the optical axis of the lens and includes a principal point on the incident light side of the lens and a plane which is normal to the optical axis of the lens and includes a principal point on the outgoing light side of the lens.

A number of lenses are provided in a lens barrel along the optical axis direction, and two lenses, among the multiple lenses, are structured so that their inclination can be adjusted independently. Tilt adjustments for a lens frame of one lens, which is arranged on the opening side of the lens barrel in the optical axis direction, can be made through an opening of the lens barrel. The other lens frame of the other lens, which is arranged in the middle of the multiple lenses, is structured so that inclination adjustments can be made through throughholes that are provided to penetrate the peripheral surface of the lens barrel in the diameter direction.