8356 results about "Optical axis" patented technology

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 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 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 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; 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 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 surface of the image source side of the seventh lens is a convex surface; the surface curvature radius R7 of the projection side of the fourth lens and the surface curvature radius R8 of the image source side of the fourth lens meet the following formula:-0.6 lt; (R7-R8) / (R7 + R8) lt; 0. 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, 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 positive focal power; 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 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 image side surface of the eighth lens is a concave surface near the optical axis. 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 concave 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 fourth lens has positive focal power; the fifth lens has positive focal power, and the object 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.

An aperture unit having an optical axis is provided, which includes a fixed portion having a first surface and including a protrusion formed on the first surface, a guiding element movably connected to the fixed portion and including a through hole, a first blade movably connected to the guiding element and the fixed portion, and a driving assembly use for driving the guiding element to move for moving the first blade. The optical axis passes through the through hole. The first surface has a first accommodating space having a recessed structure to accommodate the guiding element, and the protrusion extends toward the first blade.

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; the seventh lens has negative focal power; and the object side surface of the eighth lens is a convex surface, and the image side surface of the eighth lens is a convex surface. 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 invention discloses a precision aspheric part profile measurement method. The method comprises the following steps: constructing a measurement system; point cloud data acquisition: controlling relative movement of a spectrum confocal sensor and a rotatable workpiece table in the measurement system, and acquiring three-dimensional point cloud data of the surface of the aspheric part in a spiral scanning mode or a layered annular scanning mode; performing fusion processing on the collected point cloud data, and preliminarily estimating the optical axis direction based on principal component analysis (PCA); and based on the fused point cloud data, calculating parameters such as an optical axis position and an attitude of the aspheric part, determining a curved surface equation of the optical element, calculating a transformation matrix, and performing point cloud coordinate transformation. According to the method, the spectrum confocal measurement technology is utilized, the high-precision position information aspheric part appearance measurement technology is fused, the three-dimensional appearance data of the whole surface of the aspheric part can be obtained in a non-contact and high-precision mode, and key parameters such as the optical axis of the aspheric part can be determined.

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 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 seventh lens has positive focal power; the eighth lens has positive focal power; and the ninth lens has negative 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 discloses an automatic optical prism optical axis parallelism adjusting method based on image processing, and relates to the technical field of high-end equipment optical detection. According to the scheme, a prism reflection image sequence is collected based on a calibration light source, an optical axis projection coordinate system is established, light spot geometric centroid and boundary parameters are extracted, and an optical axis direction vector matrix is constructed; calculating an optical axis included angle deviation according to the multi-frame image, and establishing an optical axis parallelism parameter model; decomposing the error distribution matrix through an iterative minimum deviation method to obtain attitude bias and system aberration components, and generating a prism attitude adjustment vector to realize closed-loop automatic adjustment; according to the invention, high-precision and self-adaptive adjustment of the optical axis parallelism can be realized under the conditions of complex illumination and device batch fluctuation, and the stability, consistency and automation level of optical system installation and adjustment are improved.

The invention provides an optical lens, which comprises four 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 convex surface; the image side surface of the fourth lens is a convex surface; wherein the maximum field angle FOV of the optical lens and the real image height IH corresponding to the maximum field angle of the optical lens meet the following conditions: 35 degrees / mmlt; fOV / IHlt; 46 degrees / mm; the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy 0.5 lt; f3 / f4lt; and 0.8. 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 an ultra-wide angle, a large aperture, high imaging quality, high collimation and the like.

The invention relates to an optical distortion test system and method. According to the method, a light source assembly is used for outputting projection light; the target assembly is fixed in front of the projection light output end of the light source assembly. The to-be-tested assembly is located on the side, away from the light source assembly, of the target assembly and connected with the adjusting assembly. The adjusting assembly comprises a pitching adjusting sub-assembly, a horizontal adjusting sub-assembly, a height adjusting sub-assembly and an inclined sub-assembly, the pitching adjusting sub-assembly is used for ensuring that the to-be-detected assembly is perpendicular to the projection optical axis, and the horizontal adjusting sub-assembly and the height adjusting sub-assembly are used for ensuring that the optical center of the to-be-detected assembly is coaxial with the projection optical axis and the lens center of the detection assembly; the inclined sub-assembly is used for adjusting a space angle between an optical central axis of the to-be-detected assembly and a projection optical axis of the light source assembly so as to detect edge distortion of the to-be-detected curved surface element; the detection assembly is located on the side, away from the to-be-detected assembly, of the adjusting assembly and used for shooting a projection image of the target assembly which generates distortion after being acted by the to-be-detected assembly.

Various implementations disclosed herein include devices, systems, and methods that initiate an action based on a detected gaze direction oriented towards a target area (e.g., a hot corner / zone). For example, an example process may include producing a reflection by directing light towards an eye using an illuminator, receiving sensor data from a sensor, wherein a direction of sensing by the sensor (e.g., the optical axis of the camera) and a direction from the eye to a target area are approximately aligned, determining a reflective property (e.g., a spectral property) of the reflection based on the sensor data, detecting that a gaze direction of the eye is approximately oriented towards the target area (e.g., a hot zone / spot) based on the reflective property, and initiating an action based on detecting that the gaze direction is approximately oriented towards the target area.

A vehicle lamp includes a light source, and a lens. The lens includes a central region centered on an optical axis of the lamp and a peripheral region located around the central region. A rear surface of the peripheral region is formed with plural total reflection prism elements which reflects light emitted from the light source toward the front of the vehicle lamp in a state of being aligned in a concentric circular form centered on the optical axis. The rear surface of the peripheral region includes an inner periphery-side region and an outer periphery-side region. The plurality of total reflection prism elements form a first annular concave curved surface centered on the optical axis as an envelope surface in the inner periphery-side region and form a second annular concave curved surface centered on the optical axis as an envelope surface in the outer periphery-side region.

The invention is suitable for the technical field of gas concentration monitoring, and provides a high-precision gas detection self-adaptive light intensity noise suppression system and method, and the system comprises a detection module, a gas input module and an adjustment module. The system is compact in structure, not only effectively inhibits multi-scale light intensity noise introduced by a laser light source, but also remarkably improves the detection precision on the premise of guaranteeing quick response of the system. Light intensity noise is sensed by adopting a common-optical-axis optical path design, and self-adaptive suppression of the light intensity noise is realized in combination with a dual-time-scale noise feature extraction method. The method has a quick response capability while maintaining high precision, and provides a high-reliability detection means for oil-gas exploration, safety production and other scenes.

The invention relates to the field of automobile electronic testing technology and equipment, and discloses a vehicle-mounted camera imaging quality testing method and device suitable for a rain and fog scene, and the method comprises the steps: installing a to-be-tested camera module in a rain and fog environment cabin, setting the spectrum and illumination of a top natural illumination simulation system, and simulating the illumination at different time periods; selecting a test target plate in the darkroom; starting an automatic centering module to align the optical axis with the standard plate reference; rain and fog parameters are set through the environment control host, the rain and fog supply system is started to simulate different levels of rain and fog environments, and the raindrop particle size, concentration, dripping speed, fog visibility and fogdrop particle size are dynamically regulated and controlled; shooting a target plate graph card, extracting characteristic parameters by an image analysis module, performing quantitative analysis, and generating an evaluation report, so as to solve the technical problem of singleness of rain and fog scene environment simulation in the prior art.

The invention relates to a light curtain. The wiring workability under the condition that an operation indicating lamp is arranged on a light curtain of an optical synchronization system is improved. The light curtain includes a synchronization unit (optical axis for timing synchronization) for synchronizing the light projection timing of the light projector and the light reception timing of the light receiver by optical communication. A safety signal generated on the basis of whether or not an optical axis formed between the light projector and the light receiver is in a light-shielding state is output to the outside. The light curtain comprises a first operation indicating lamp arranged in the light projector; the second operation indicating lamp is arranged in the light receiver; an optical element (optical axis) provided in each of the light projector and the light receiver and configured to display the first operation indicator light and the second operation indicator light in conjunction with each other; and a control circuit configured to display the first operation indicating lamp and the second operation indicating lamp in linkage by using at least one group of optical elements.

The invention relates to the technical field of projection, and discloses a method, a device and equipment for measuring a projection ratio and an off-axis ratio, and a medium. The method comprises the following steps: acquiring a projection test image obtained by sampling a projection area and a reference area by an image sampling device of the projector; performing area feature extraction processing on the projection test image to obtain image size information and central point pixel information of a projection area and image size information of a reference area; determining the projection ratio of the projector based on the image size information of the projection area, the projection distance information of the projector and the image size information and the actual size information of the reference area; and determining the off-axis ratio of the projector based on the central point pixel information of the projection area, the optical axis pixel information of the projector and the image size information and the actual size information of the reference area. According to the embodiment of the invention, the cost of measuring the projection ratio and the off-axis ratio can be reduced.

The invention discloses a compact internal focusing type standard photographic lens and a photographic device. The photographic lens sequentially comprises a first lens group with positive focal power, an aperture diaphragm, a second lens group with positive focal power and a third lens group with negative focal power from an object side to an image side, in the focusing process, the second lens group moves along the optical axis, and the first lens group and the third lens group remain unchanged relative to the position of the image plane. The first lens group, the second lens group and the third lens group satisfy the following conditional expressions: 1 < = F1 / F < = 2; 0.2 < = F2 / F < = 1; -3 < = F3 / F < = 0; wherein F1 represents the composite focal length of the first lens group, F2 represents the composite focal length of the second lens group, F3 represents the composite focal length of the third lens group, and F represents the focal length of the photographic lens. The compact internal focusing type standard photographic lens provided by the technical scheme of the invention is beneficial to optimization of optical performance, focusing mechanism, positive and negative focal power balance and simplification of design and manufacturing of the lens.

The invention provides a production equipment state real-time analysis method and system based on edge calculation, and relates to the technical field of information, and the method comprises the steps: analyzing the dynamic change trend of a light beam central axis according to the offset trajectory of the light beam central axis, and determining the spatial distribution characteristics of the light beam axis through the dynamic change trend of the light beam central axis in combination with an LED array arrangement SIC mode; if the adjustment angle in the lens calibration instruction set exceeds a preset angle threshold, dynamically adjusting the position of the optical axis of the lens according to the offset amplitude and direction of the optical axis, compensating the offset of the light beam axis in real time, and obtaining a calibrated optical axis parameter; according to the color temperature distribution uniformity, determining a target lens position through a lens position adjustment attribute; according to the calibrated optical axis parameters and color temperature distribution uniformity, stable light beam center axis distribution is determined, spectrum consistency is determined, and a performance evaluation data set is obtained through comprehensive evaluation.

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; the surface of the projection side of the second lens is a convex surface, and the surface of the image source side of the second lens is a convex surface; 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 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; and the surface of the projection side of the seventh lens is a convex surface. 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 discloses a carrier of a camera module, a manufacturing method and the camera module, the carrier of the camera module comprises a main body, the main body comprises a plurality of side parts, each side part is arranged around the optical axis of the camera module, a corner part is formed at the joint of two adjacent side parts, and the main body is subjected to first injection molding and has first rigidity; the insert is wrapped on the main body, and the insert is made of a metal material; the buffering part is formed at the corner part through secondary injection molding, the buffering part comprises a buffering section, the buffering section protrudes out of the surface of the main body in the movement direction of the carrier, the buffering part has second rigidity, and the second rigidity is smaller than the first rigidity. Through the first injection molding and the second injection molding, high integration of the main body, the insert and the buffer part can be realized, in other words, the integration of the carrier can be improved, the overall size of the carrier is effectively reduced, meanwhile, the supply chain and the assembly process of the carrier are simplified, the production efficiency of the carrier and the camera module is improved, and the manufacturing cost is reduced.

The invention belongs to the field of optical detection, and particularly relates to a synchronous calibration method for a geometric pose and an optical axis error of a reflective phase deflection system, which comprises the following steps of: taking a plane mirror pose as a reference, establishing redundant geometric constraints under a plurality of poses through mirror image reflection, and jointly solving geometric external parameters of the system; and meanwhile, a reverse ray tracing model and a normal integral model are synchronously constructed in a calibration stage, surface shape data are actually measured by combining an interferometer, a system optical axis error field is explicitly stripped, and decoupling separation of a system structure error and a surface shape error is realized. According to the method, the system building process is greatly simplified, the dependence of a high-precision mechanical auxiliary device is avoided, and the overall detection precision and the low-frequency error control capability of the reflective phase deflection system are effectively improved by synchronously modeling and compensating the optical axis error of the system in the calibration stage; and a technical basis with engineering adaptability is provided for high-precision free-form surface optical detection.

The invention belongs to the technical field of telescope manufacturing, and discloses a large-view-field telescope optical system which is characterized in that a first objective lens, a second objective lens, a third objective lens, a focusing lens, a semi-pentaprism, a roof prism, a first eyepiece lens, a second eyepiece lens and a third eyepiece lens are sequentially designed from the object side to the image side in the optical axis direction. According to the optical system, only the ten lenses have diopters, the requirement for the field of view of 6.7 degrees under the 8-fold condition is met, and the exit pupil distance reaches 22.6 mm.

The invention relates to the technical field of optics, in particular to a projection lens, a projection system and electronic equipment. The projection lens comprises a first lens group, an aperture diaphragm and a second lens group which are sequentially arranged from a projection surface to an image source surface along an optical axis, the first lens group has negative focal power, and the second lens group has positive focal power; the first lens group consists of a first lens, a first sub-lens group and a diaphragm front lens which are sequentially arranged from a projection surface to an image source surface along an optical axis; the first sub-lens group comprises at least one lens with negative focal power; the first lens and the diaphragm front lens respectively have positive focal power, and the first sub-lens group has negative focal power; the second lens group consists of a diaphragm rear lens and a second sub-lens group which are sequentially arranged from the projection surface to the image source surface along the optical axis; the second sub-lens group has positive focal power and comprises a group of balsaming lenses with positive focal power, and the diaphragm rear lens has negative focal power. The focusing range of the projection lens is larger than or equal to 500 mm.

The invention provides a lens optical axis consistency inspection device and a detection method thereof, and relates to the technical field of lens optical axis consistency, and the lens optical axis consistency inspection device comprises an optical platform as an installation reference, a target plate structural member which is fixed on the platform and is provided with a first cross mark, and a fixed seat structural member which is spaced from a target plate by a preset distance and is used for installing a to-be-detected lens module. The method is characterized in that the lens optical axis consistency is evaluated by comparing the position deviation between a target plate mark image acquired by a lens module and a second mark generated by a sensor. According to the invention, a simple mechanical structure is used for replacing a traditional expensive and complex instrument, and through a unique double-label comparison principle, not only can rapid qualitative screening be realized, but also accurate quantitative calculation can be carried out. The device has the outstanding advantages of low cost, simplicity and convenience in operation and high detection efficiency. The design effectively solves the problem of rapid detection of the consistency of the batch lens centers of the production line, significantly reduces the detection threshold and cost, and is of great significance to the improvement of the product quality control level.

The invention provides a projection 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 a projection surface to an image source surface along an optical axis, 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 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 seventh lens has positive focal power; wherein the surface curvature radius R1 of the projection side of the first lens and the surface curvature radius R2 of the image source side of the first lens meet the following formula:-0.8 lt; (R1 + R2) / (R1-R2) lt; and 0.5. 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.