15649 results about "Optical axis" patented technology

The invention discloses an optical lens which is sequentially arranged from an object side to an image side along an optical axis of the lens: a first lens which is a glass lens with negative focal power; the second lens has negative focal power; the third lens is provided with positive focal power; a fourth lens, wherein the fourth lens has positive focal power or negative focal power; an aperture stop; a fifth lens, wherein the fifth lens has a positive focal power or a negative focal power; a sixth lens having a positive focal power or a negative focal power; a seventh lens having a positive focal power or a negative focal power; and the eighth lens is a plastic lens with positive focal power or negative focal power. The lens is formed by mixing glass and plastic, the field angle is larger than or equal to 200 degrees, the aperture is larger than or equal to 1.9, and the lens has the advantages of being large in field of view, large in aperture, high in imaging quality and high in brightness.

A gimbal includes a first driver mechanism configured to drive a photographing device to rotate around a first rotation axis, a base connected to the first driver mechanism, a second driver mechanism connected to the base, and an arc-shaped shaft arm. An accommodation space is provided on one side of the arc-shaped shaft arm that is close to an axis of the arc-shaped shaft arm. The accommodation space is configured to accommodate the photographing device in a manner that an optical axis of the photographing device is non-parallel to the axis of the arc-shaped shaft arm. The second driver mechanism is connected to the arc-shaped shaft arm and configured to drive the photographing device to slide relatively along the arc-shaped shaft arm and rotate relative to a second rotation axis.

The invention provides a multi-layer optical film detection method, device and equipment and a storage medium, and the method comprises the steps: obtaining a polarization phase difference signal of transmission light and reflected light through multi-angle incidence irradiation of a multi-band programmable laser source, and recording the polarization ellipticity parameter change; then combining confocal microscopic interference and polarization analysis to determine a space coordinate and a stress distribution diagram of a stress abnormal region; continuously irradiating in a photo-thermal coupling environment through a broadband light source, and monitoring interference signals, polarization states and temperature changes to obtain dynamic evolution characteristics; and finally, performing a simulation test on the multi-layer optical film in a system environment with preset optical axis arrangement and light beam energy distribution, obtaining an in-situ polarization state and interference pattern data, and evaluating the optical performance of the film layer. According to the invention, potential defects can be positioned under high resolution, and the reliability and imaging quality of the film layer under complex application conditions can be accurately evaluated.

The invention discloses absolute pointing equipment, an absolute pointing method and interactive equipment. In order to solve the problems of high power consumption, low real-time performance and high cost in the existing scheme, a DVS is arranged in a pointing device and is used for sensing a flicker light source arranged on a pointed device; the pointed device is provided with three or more flickering light sources, and at least three flickering light sources are not collinear. Filtering the event stream output by the DVS, extracting pixel coordinates associated with the flicker light sources, and identifying the identifier of each flicker light source; obtaining a pose parameter of the camera according to the pixel coordinates associated with the flicker light source, and obtaining optical axis information of the camera according to the pose parameter of the camera; according to the optical axis information of the camera, obtaining coordinate information of an intersection point of the optical axis of the camera and the coplanar where the at least three flickering light sources are located; and the pointed device executes a corresponding response according to the coordinate information of the intersection point. The method has the advantages of low cost, low power consumption and high real-time performance.

The invention discloses an image analysis method and system for concrete apparent quality defect detection, and relates to the technical field of concrete apparent quality defect detection.The method comprises the steps that a camera device is used for collecting concrete surface images in a specified distance interval, and the optical axis of a camera lens is controlled to be perpendicular to the concrete surface; carrying out image preprocessing on the collected concrete surface image, and carrying out defect type image marking; carrying out key feature extraction on the preprocessed concrete surface image by adopting a convolutional neural network to obtain key feature information; constructing a multi-algorithm comparison verification framework, performing cross validation in combination with the key feature information to obtain defect detection results and evaluation results of a plurality of defect detection models, optimizing model parameters in combination with a confusion matrix, and determining a final concrete surface detection model; obtaining an apparent quality defect detection result based on the defect detection result and a preset quality defect grading threshold value; the efficiency of concrete apparent defect detection is improved.

The invention provides an optical lens, which comprises seven lenses from an object side to an imaging surface along an optical axis: a first lens with positive focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with positive focal power and a sixth lens with negative focal power, the object side surface of the second lens near the optical axis is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface near the optical axis; the object side surface of the fourth lens is a convex surface near the optical axis, and the image side surface of the fourth lens is a concave surface near the optical axis; the object side surface of the fifth lens is a concave surface near the optical axis, and the image side surface of the fifth lens is a concave surface near the optical axis; the sixth lens has positive focal power, the object side surface of the sixth lens is a convex surface near the optical axis, and the image side surface of the sixth lens is a concave surface near the optical axis; and the object side surface of the seventh lens is a convex surface near the optical axis, and the image side surface of the seventh lens is a concave surface near the optical axis. The optical lens provided by the invention has one or more advantages of short total length, large aperture, small distortion and the like.

The invention provides an optical lens, which comprises seven lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a convex surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a convex surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a concave surface; the object side surface of the sixth lens is a convex surface, and the image side surface of the sixth lens is a concave surface; and the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a concave surface. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, the aberration can be reduced, the imaging quality of the optical lens can be improved, and the lens has one or more advantages of large target surface, large aperture, high imaging quality and the like.

A line-of-sight direction tracking method includes: providing corneal reflection for an eye of a user by using a plurality of light sources, and capturing images including a face of the user by using a plurality of cameras; determining coordinates of a light source reflection point and coordinates of a pupil center in a world coordinate system by means of a human eye feature set acquired from the images including the face, based on hardware calibration parameters; determining a line-of-sight optical axis according to the coordinates of the light source reflection point and the coordinates of the pupil center, and reconstructing, based on the line-of-sight optical axis, a line-of-sight visual axis by means of a compensation angle; and determining a point of sight on a target object according to the line-of-sight visual axis and a position of the target object in the world coordinate system.

An optical element driving mechanism is provided. The optical element driving mechanism includes a movable portion, a fixed portion and a driving component. The movable portion is connected to an optical element having an optical axis. The movable portion is movable relative to the fixed portion. The driving component is configured to drive the movable portion to move relative to the fixed portion in a first dimension.

The invention provides an optical lens, which comprises nine lenses from an object side to an imaging surface along an optical axis: a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the sixth lens has negative focal power; the seventh lens has positive focal power; the eighth lens has negative focal power; and the ninth lens has positive focal power. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the lens has one or more advantages of short focus, miniaturization, large field angle, large aperture, large target surface, low distortion and low sensitivity.

The invention provides an optical lens, which comprises eight lenses with focal power and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface; the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface; and the object side surface of the eighth lens is a convex surface, and the image side surface of the eighth lens is a concave surface. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, and the optical lens has the advantage of excellent imaging quality.

The invention provides an optical lens, which comprises eight lenses with focal power and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; the seventh lens has positive focal power, and the object side surface of the seventh lens is a convex surface; and the image side surface of the eighth lens is a convex surface. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, and the optical lens has the advantage of excellent imaging quality.

The invention provides an optical lens, which comprises eight lenses with focal power and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the sixth lens has negative focal power, and the image side surface of the sixth lens is a concave surface; the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface; and the object side surface of the eighth lens is a concave surface. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, and the optical lens has the advantage of excellent imaging quality.

The present invention relates to an aperture unit having an optical axis. The aperture unit includes a fixed portion, a guiding element, a first blade and a driving assembly. The guiding element is movably connected to the fixed portion, and the first blade is movably connected to the guiding element and the fixed portion. The driving assembly is disposed on the guiding element for driving the guiding element to move relative to the fixed portion in a first moving dimension. When the guiding element moves relative to the fixed portion in the first moving dimension, the first blade is driven by the guiding element to move relative to the fixed portion in a second moving dimension, and the first moving dimension and the second moving dimension are different.

The invention relates to a satellite-borne laser communication terminal in-orbit optical axis rapid calibration method, and aims to improve the pointing precision and stability of a satellite-borne laser communication system. According to the method, the optical axis of the laser communication terminal is quickly and accurately calibrated by comprehensively applying technical means such as coordinate system conversion, an error correction matrix, least square method optimization and a golden section method. According to the method, complex coordinate system conversion and an error correction matrix are comprehensively applied, and high-precision correction of a theoretical pointing vector is achieved; the golden section method is combined with the optimization strategy of the least square method, so that the convergence speed and precision of the calibration process are improved; higher real-time performance and automation degree are achieved, related data can be acquired and processed in real time, and real-time correction of the optical axis pointing error is achieved; the method has wide applicability and expandability, and can be applied to other spacecraft systems needing high-precision pointing control.

The invention provides an optical lens, which comprises seven lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with positive focal power and a fifth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the image side surface of the fourth lens is a convex surface; the fifth lens has positive focal power, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens near the optical axis is a convex surface; and the object side surface of the seventh lens is a concave surface near the optical axis, and the image side surface of the seventh lens is a convex surface. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the imaging quality of the optical lens is improved, and the lens has one or more advantages of ultra wide angle, ultra large aperture, large image plane, high pixel, high imaging quality and the like.

The utility model discloses an optical lens. The optical lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seventh lens and an eighth lens from an object side to an image side along an optical axis, the first lens has negative focal power, the object side surface is a convex surface, and the image side surface is a concave surface; the second lens has negative focal power, the object side surface of the second lens is a convex surface, and the image side surface is a concave surface; the third lens has negative focal power, and the object side surface of the third lens is a concave surface; the fourth lens has positive focal power, the object side surface of the fourth lens is a convex surface, and the image side surface is a convex surface; the object side surface of the fifth lens is a convex surface; the image side surface of the sixth lens is a convex surface; the seventh lens has negative focal power, and the object side surface of the seventh lens is a concave surface; the eighth lens has positive focal power, the object side surface of the eighth lens is a convex surface, and the image side surface is a convex surface; wherein the combined effective focal length Fa of the first to fourth lenses and the total effective focal length F of the optical lens meet the condition that Fa / F is greater than or equal to-4.1 and less than or equal to-2.2.

The invention provides an optical lens, which comprises seven lenses in total, and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a concave surface, and the image side surface of the third lens is a convex surface; the object side surface of the fourth lens is a convex surface, and the image side surface of the fourth lens is a concave surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; and the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a concave surface. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, the aberration can be reduced, the imaging quality of the optical lens can be improved, and the lens has one or more advantages of large target surface, large aperture, high imaging quality and the like.

The invention provides an adjustment method of detection equipment, and the detection equipment sequentially comprises an objective lens, a spectroscope, a barrel lens and a detector from an object space to an image space, and also comprises a Kohler illumination module. The illumination light beam is emitted from the Kohler illumination module and is transmitted to the objective lens through the spectroscope, when the object to be detected is arranged on one side, far away from the spectroscope, of the objective lens, the illumination light beam emitted from the objective lens is reflected to obtain a reflected light beam, and the reflected light beam sequentially passes through the objective lens, the spectroscope and the barrel lens to reach the detector. After an aperture diaphragm is inserted into the Kohler illumination module and an auxiliary lens is arranged between the barrel lens and the detector, obtaining a first light spot position of a light spot formed by the aperture diaphragm at an entrance pupil of the objective lens through the detector; and under the condition that the Kohler illumination module does not provide the illumination light beam and the light source is used as an object to be detected, acquiring a second light spot position of the light spot of the entrance pupil of the objective lens through the detector, adjusting the position of the aperture diaphragm according to the first light spot position and the second light spot position, and aligning the illumination optical axis and the imaging optical axis.

The invention provides an optical imaging lens. The optical imaging lens comprises a lens barrel, a lens group and a spacing element group, and the lens group and the spacing element group are arranged in the lens barrel. The six lenses are sequentially a first lens with negative focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with positive focal power and a sixth lens with negative focal power from the object side to the image side along the optical axis of the optical imaging lens; the following conditions are satisfied: 1.00 lt; cT5 / EP45 / N5lt; 1.75, 1.75; f4 / (EP34 + CP4) is greater than or equal to-2.05 and less than or equal to-1.35; and (D5m-d4s) / CP5 is more than or equal to 3.59 and less than or equal to 5.60. According to the invention, the problem that the size of the lens is increased due to the fact that a six-piece optical imaging lens in the prior art meets the performance requirement, and thus discretization is caused is solved.

The invention provides an optical lens, which comprises eight lenses with focal power and sequentially comprises a first lens with negative focal power, a second lens with negative focal power, a third lens with positive focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens has negative focal power, and the image side surface of the third lens is a concave surface; the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the object side surface of the sixth lens is a concave surface, and the image side surface of the sixth lens is a concave surface; the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a convex surface; and the object side surface of the eighth lens is a concave surface. According to the optical lens provided by the invention, the imaging quality of the optical lens can be improved, and the optical lens has the advantage of excellent imaging quality.

The invention provides an optical imaging lens. The optical imaging lens comprises a lens barrel, a lens group and a spacing assembly, wherein the lens group and the spacing assembly are accommodated in the lens barrel; the lens group comprises a first lens with negative focal power, a second lens with positive focal power, a third lens with negative focal power, a fourth lens with positive focal power and a fifth lens with negative focal power which are sequentially arranged from the object side to the image side along the optical axis. The sixth lens has positive focal power; the seventh lens has negative focal power; the spacing assembly comprises a second spacing element which is arranged between the second lens and the third lens and is in contact with the image side surface of the second lens, and a third spacing element which is arranged on the image side of the third lens and is in contact with the image side surface of the third lens; the optical imaging lens satisfies the following conditions: 7.69 mm < = f * tan (HFOV) < = 9.27 mm, and 33.65 < EP23 / T23 < 59.35.

The invention provides an optical lens, which comprises eight lenses with focal power and sequentially comprises a first lens with negative focal power, a second lens with positive focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power from an object side to an imaging surface along an optical axis, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the third lens has negative focal power, the object side surface of the third lens near the optical axis is a convex surface, and the image side surface of the third lens is a concave surface; the fourth lens has positive focal power; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the sixth lens has positive focal power, and the image side surface of the sixth lens is a convex surface; the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface; and the eighth lens has positive focal power. The optical lens provided by the invention has one or more advantages of short focus, large field angle, high imaging quality and the like.

The zoom lens comprises a focusing lens group, a zoom lens group and a fixed lens group which are sequentially arranged from an object plane to an image plane along an optical axis, the focusing lens group has negative focal power, the zoom lens group has positive focal power, and the fixed lens group has positive focal power. The focusing lens group comprises a first lens, a second lens, a third lens and a fourth lens which are sequentially arranged from an object plane to an image plane; the zoom lens group comprises a fifth lens, a sixth lens, a seventh lens, an eighth lens and a ninth lens which are sequentially arranged from the object plane to the image plane; the fixed lens group includes a tenth lens. According to the zoom lens provided by the embodiment of the invention, a three-component structure is adopted, ten lenses are used, the number of the lenses in the three lens groups is set, and the focal power matching of the three lens groups and the ten lenses is further limited, so that the high-image-quality zoom lens which is small in size, large in aperture, infrared and confocal at high and low temperatures is realized, and the zoom lens can be matched with a 1 / 1.8 ''chip for use.

The invention provides an optical lens, and the optical lens sequentially comprises a first reflection element with positive focal power from an object side to an imaging surface, the first reflection element comprises an incident surface, a reflection surface and an emergent surface, the incident surface of the first reflection element is a convex surface, and the emergent surface of the first reflection element is a convex surface; included angles of 45 degrees are respectively formed between the reflecting surface of the first reflecting element and the optical axes of the incident surface and the emergent surface of the first reflecting element; the second lens has focal power; the third reflecting element has focal power and comprises an incident surface, a reflecting surface and an emergent surface; included angles of 45 degrees are respectively formed between the reflecting surface of the third reflecting element and the optical axes of the incident surface and the emergent surface of the third reflecting element; and the fourth lens has negative focal power. The optical lens provided by the invention adopts two reflecting elements with diopters as light path turning elements, so that a light path is turned twice to realize periscopic telephoto, and the optical lens has the characteristics of small volume, large aperture, large target surface and good performance.

The invention discloses an outdoor distribution box inspection system and method based on path planning. The system comprises a master control terminal, an inspection unmanned aerial vehicle, an unmanned aerial vehicle landing base station and a distributed RTK positioning module. Wherein the main control terminal integrates an image processing unit and a dynamic path planning engine, and interacts with the patrol unmanned aerial vehicle in real time through a wireless communication protocol; the patrol unmanned aerial vehicle carries a dual-mode visual system and comprises a vertically downward path planning camera and an acquisition camera for direction adjustment of a holder, and the holder dynamically adjusts the orientation of the acquisition camera based on real-time position feedback of the RTK module to ensure that the optical axis of the holder is always aligned with the RTK module at the top of the nearest distribution box.

The invention relates to the technical field of focus testing, and particularly discloses a laser cutting head zero focus testing method based on reflected light detection, which comprises the following steps: S1, acquiring an optical signal reflected by a processed plate in a cutting process; s2, adjusting the position of a focusing lens to enable a laser focus to move along the optical axis direction relative to the surface of the plate; s3, recording reflected light intensity values corresponding to different focus positions, obtaining a function relationship between the reflected light intensity and the focus positions, and drawing a light intensity-focus position relationship curve; s4, determining a corresponding focus position when the intensity of the reflected light reaches the maximum value as an optical zero focus position of the system; s5, automatically recording and storing an optical zero focus position; the reflected light detector arranged in the cutting head or the laser reads the intensity of the reflected light in the cutting process, the function relation between the focus position and the intensity of the reflected light can be established, and the focus position corresponding to the maximum value of the intensity of the reflected light is the most accurate optical zero focus position.

The invention provides an optical lens, which comprises nine lenses from an object side to an imaging surface along an optical axis: a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power, a fifth lens with negative focal power and a sixth lens with negative focal power, the object side surface of the second lens is a convex surface, and the image side surface of the second lens is a concave surface; the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a concave surface; the object side surface of the fourth lens is a concave surface, and the image side surface of the fourth lens is a convex surface; the object side surface of the fifth lens is a convex surface, and the image side surface of the fifth lens is a convex surface; the sixth lens has negative focal power; the seventh lens has positive focal power; the eighth lens has negative focal power; and the ninth lens has positive focal power. According to the optical lens provided by the invention, through specific surface shape matching and reasonable focal power distribution, the lens has one or more advantages of short focus, miniaturization, large field angle, large aperture, large target surface, low distortion and low sensitivity.

The invention provides a projection lens, which comprises seven lenses from a projection surface to an image source surface along an optical axis: a first lens with negative focal power, a second lens with negative focal power, a third lens with negative focal power, a fourth lens with negative focal power and a fifth lens with negative focal power, the second lens has positive focal power; the surface of the image source side of the third lens is a convex surface; the surface of the projection side of the fourth lens is a concave surface, and the surface of the image source side of the fourth lens is a convex surface; the surface of the projection side of the fifth lens is a concave surface, and the surface of the image source side of the fifth lens is a concave surface; the surface of the projection side of the sixth lens is a convex surface, and the surface of the image source side of the sixth lens is a convex surface; the surface of the projection side of the seventh lens is a convex surface, and the curvature radius R7 of the surface of the projection side of the fourth lens and the curvature radius R8 of the surface of the image source side of the fourth lens meet the formula:-0.5 lt; (R7-R8) / (R7 + R8) lt; and-0.1. According to the projection lens provided by the invention, the projection quality of the projection lens is improved through the reasonable configuration of the surface types of the lenses and the reasonable matching of the focal power.

The invention provides an optical lens. The optical lens comprises a lens barrel, and a lens group and a spacing assembly which are accommodated in the lens barrel; the lens group comprises a first lens with negative focal power, a second lens with positive focal power, a third lens with positive focal power, a fourth lens with positive focal power, a fifth lens with positive focal power, a sixth lens with negative focal power and a seventh lens with negative focal power which are sequentially arranged from the object side to the image side along the optical axis; the center thickness of the second lens is larger than the center thickness of other lenses in the lens group, and the maximum thickness of a non-light-transmitting area of the second lens is larger than the maximum thickness of non-light-transmitting areas of other lenses. The spacing assembly comprises a second spacing element, a third spacing element, a fourth spacing element and a fifth spacing element; the optical lens satisfies the following conditions: 1.60 < L / (f * tan (Semi-FOV)) < 1.95; (CT2 + CT4) / CT3 is more than 5.55 and less than 7.50; 5.90 < = D5s / d2slt; 7.00 and 6.70 < EP02 / EP23 < 8.65.