Patents by Inventor Jonas Hjelmstrom
Jonas Hjelmstrom has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Publication number: 20180188634Abstract: A method for sequential control of a diaphragm arrangement of a camera, the arrangement comprising a diaphragm, and an integrated IR cut filter always covering at least a portion of an aperture opening of the diaphragm, comprising: initiating closing or opening of the diaphragm; detecting an amount of incident radiation when the diaphragm has an initial aperture opening; shifting the aperture opening to an intermediate aperture opening to alter the ratio between visible light and infrared radiation passing the diaphragm; detecting an amount of incident radiation following the shift; calculating a composition of visual light and infrared radiation in the scene from the detected amounts of incident radiation and a calculated ratio between visible light and infrared radiation when having the initial aperture opening and the intermediate aperture opening, respectively; and shifting the aperture opening of the diaphragm to a new position.Type: ApplicationFiled: December 28, 2017Publication date: July 5, 2018Applicant: Axis ABInventors: Stefan Lundberg, Jonas Hjelmström
-
Publication number: 20180180783Abstract: An infrared (IR) filter arrangement for a camera having an associated IR illuminator, the arrangement comprising: a fixedly arranged bandpass IR filter filtering out IR frequencies other than those from the IR illuminator; and an IR cut filter at least blocking any IR wavelength transmitted by the fixed band-pass filter, the IR filter being integrated in a diaphragm of the camera, such that closing of the diaphragm aperture entails an increased relative proportion of the diaphragm aperture being covered by the IR cut filter, and opening of the diaphragm aperture entails a decreased relative proportion of the diaphragm aperture being covered by the IR cut filter.Type: ApplicationFiled: December 28, 2017Publication date: June 28, 2018Applicant: Axis ABInventors: Jonas Hjelmström, Stefan Lundberg
-
Publication number: 20180184054Abstract: A camera comprising: an aperture; an image sensor comprising a plurality of pairs of pixels where in each pair: a first pixel is configured such that it detects radiation which has entered the camera through the aperture to the image sensor via a first radiation path, and a second pixel is configured such that it detects radiation which has entered the camera through the aperture to the image sensor via a second radiation path, the second radiation path being different from the first radiation path; and a filter arranged in the vicinity of the aperture, wherein the filter comprises a first portion configured to block IR-radiation or visible light and a second portion configured to be transparent to wavelengths that are blocked by the first portion, wherein radiation passing the first portion travels to the first pixels, and radiation passing the second portion travels to the second pixels.Type: ApplicationFiled: December 28, 2017Publication date: June 28, 2018Applicant: Axis ABInventors: Stefan Lundberg, Jonas Hjelmström
-
Publication number: 20180124329Abstract: A method and apparatus for determining a focal-length setting of a lens mounted to a camera. In a method for determining a focal-length of a lens mounted to a camera, a distorted image of a scene is captured. A distortion-correction function is applied on the distorted image or on a portion of the distorted image. A most representative distortion-correction function is identified and a current focal-length setting for the lens is identified by correlating the identification to a data compilation.Type: ApplicationFiled: December 22, 2017Publication date: May 3, 2018Applicant: Axis ABInventors: Jonas Hjelmström, Andreas Nilsson
-
Patent number: 9936112Abstract: The present application relates to a camera where a non-wide-angle lens and a wide-angle lens projects images onto different regions of one and the same image sensor. The non-wide-angle lens images a part of a periphery of the wide-angle lens image, and in this way an overview image with an improved quality peripheral region can be achieved.Type: GrantFiled: March 8, 2016Date of Patent: April 3, 2018Assignee: Axis ABInventors: Jonas Hjelmström, Stefan Lundberg, Andreas Karlsson Jägerman
-
Patent number: 9888187Abstract: A method and apparatus for determining a focal-length setting of a lens mounted to a camera is disclosed. In a method for determining a focal-length of a lens mounted to a camera, a distorted image of a scene is captured. A distortion-correction function is applied on the distorted image or on a portion of the distorted image. A most representative distortion-correction function is identified and a current focal-length setting for the lens is identified by correlating the identification to a data compilation.Type: GrantFiled: April 1, 2016Date of Patent: February 6, 2018Assignee: Axis ABInventors: Jonas Hjelmström, Andreas Nilsson
-
Patent number: 9538053Abstract: A protective camera enclosure (3) for a monitoring camera (1) comprises a cover portion (5) which is selectively moveable, in response to a detected tampering threat, from a retracted configuration exposing the camera (1) to an extended configuration covering and physically protecting the camera (1).Type: GrantFiled: November 20, 2014Date of Patent: January 3, 2017Assignee: AXIS ABInventors: Niklas Lindman, Jonas Hjelmstrom
-
Publication number: 20160301836Abstract: The present application relates to a camera where a non-wide-angle lens and a wide-angle lens projects images onto different regions of one and the same image sensor. The non-wide-angle lens images a part of a periphery of the wide-angle lens image, and in this way an overview image with an improved quality peripheral region can be achieved.Type: ApplicationFiled: March 8, 2016Publication date: October 13, 2016Applicant: AXIS ABInventors: Jonas Hjelmström, Stefan Lundberg, Andreas Karlsson Jägerman
-
Publication number: 20160295115Abstract: In a method for image stabilization a number of operations are performed to stabilize an image and to output a focal length value. The steps include capturing video by means of a video camera with unknown focal length running an image stabilization process operating on an input from a hardware detector detecting the displacement of the camera and on an adjustable focal length value. Inter-image displacement is corrected based on the input from the hardware detector and the adjustable focal length value. By evaluating the displacement and adjusting the focal length value until a satisfactory image stabilization is achieved a value of the focal length may be output.Type: ApplicationFiled: February 22, 2016Publication date: October 6, 2016Applicant: AXIS ABInventors: Jonas Hjelmström, Andreas Nilsson
-
Publication number: 20160295131Abstract: A method and apparatus for determining a focal-length setting of a lens mounted to a camera is disclosed. In a method for determining a focal-length of a lens mounted to a camera, a distorted image of a scene is captured. A distortion-correction function is applied on the distorted image or on a portion of the distorted image. A most representative distortion-correction function is identified and a current focal-length setting for the lens is identified by correlating the identification to a data compilation.Type: ApplicationFiled: April 1, 2016Publication date: October 6, 2016Applicant: Axis ABInventors: Jonas Hjelmström, Andreas Nilsson
-
Patent number: 9438814Abstract: The present invention relates to a method (300) for reducing stray light in an output image of a scene, said method comprising; providing (301) a camera (100) comprising a lens assembly (102, 202), providing (302) an aperture unit (103, 203) having an aperture gate (204a, 204b) in an aperture plane being orthogonal to an optical axis (OA) of said lens assembly (102, 202), said aperture gate (204a, 204b) being adjustable in said aperture plane, acquiring (303), by means of said camera (100), a plurality of images of said scene, wherein each image of said plurality of images is acquired using an unique aperture gate setting, wherein each of said unique aperture gate settings correspond to a unique combination of a position and a shape of said aperture gate (204a, 204b) in said aperture plane, analyzing (305) said plurality of images for generating data pertaining to a difference in stray light content with respect to said plurality of images, and producing (306) said output image based on said data pertaining tType: GrantFiled: April 24, 2014Date of Patent: September 6, 2016Assignee: AXIS ABInventors: Jonas Hjelmstrom, Anders Johannesson
-
Patent number: 9225881Abstract: The present invention relates to digital cameras and in particular to positioning of image sensors in digital cameras. By providing a digital camera comprising a lens system, at least one image sensor which is attached to a sensor disc and an axle to which the sensor disc is attached and wherein the axle is configured to allow manipulation thereof for adjusting the tilt of the at least one image sensor, a simple solution is provided, enabling adjustment of the image sensor position in the digital camera.Type: GrantFiled: February 6, 2012Date of Patent: December 29, 2015Assignee: Axis ABInventors: Jonas Hjelmstrom, Daniel Persson, Jan Sonnvik
-
Patent number: 9204058Abstract: A method for setting a camera exposure time of a camera is disclosed. A moving indicator is overlaid in a video sequence of images. The speed of the moving indicator corresponds to an exposure time below which objects that move at an angular speed which is slower than the indicator will be imaged by the camera as sharp. The speed of the moving indicator is adjusted such that it moves at the same speed as a moving object in the video sequence of images. The camera exposure time is then set based on the exposure time that corresponds to the speed of the moving indicator after the speed adjustment.Type: GrantFiled: June 10, 2014Date of Patent: December 1, 2015Assignee: Axis ABInventor: Jonas Hjelmstrom
-
Publication number: 20150172520Abstract: A protective camera enclosure (3) for a monitoring camera (1) comprises a cover portion (5) which is selectively moveable, in response to a detected tampering threat, from a retracted configuration exposing the camera (1) to an extended configuration covering and physically protecting the camera (1).Type: ApplicationFiled: November 20, 2014Publication date: June 18, 2015Applicant: Axis ABInventors: Niklas LINDMAN, Jonas Hjelmstrom
-
Patent number: 8937682Abstract: The present invention relates to a focusing device comprising: a lens, a lens plate, an image sensor, an image sensor plate, at least two rotatable structures, and at least two strips, wherein the lens is connected to the lens plate, the image sensor is connected to the image sensor plate, wherein each strip is arranged to be wound onto one of the rotatable structures, respectively, the rotatable structures and the strips are arranged between the lens plate and the image sensor plate, the rotatable structures and/or the strips are arranged in contact with the lens plate and the image sensor plate, and wherein a distance between the lens and the image sensor is adjusted by winding the strips onto or off the rotatable structures.Type: GrantFiled: March 18, 2013Date of Patent: January 20, 2015Assignee: Axis ABInventor: Jonas Hjelmstrom
-
Publication number: 20150002732Abstract: A method for setting a camera exposure time of a camera is disclosed. A moving indicator is overlaid in a video sequence of images. The speed of the moving indicator corresponds to an exposure time below which objects that move at an angular speed which is slower than the indicator will be imaged by the camera as sharp. The speed of the moving indicator is adjusted such that it moves at the same speed as a moving object in the video sequence of images. The camera exposure time is then set based on the exposure time that corresponds to the speed of the moving indicator after the speed adjustment.Type: ApplicationFiled: June 10, 2014Publication date: January 1, 2015Applicant: Axis ABInventor: Jonas HJELMSTROM
-
Publication number: 20140320686Abstract: The present invention relates to a method (300) for reducing stray light in an output image of a scene, said method comprising; providing (301) a camera (100) comprising a lens assembly (102, 202), providing (302) an aperture unit (103, 203) having an aperture gate (204a, 204b) in an aperture plane being orthogonal to an optical axis (OA) of said lens assembly (102, 202), said aperture gate (204a, 204b) being adjustable in said aperture plane, acquiring (303), by means of said camera (100), a plurality of images of said scene, wherein each image of said plurality of images is acquired using an unique aperture gate setting, wherein each of said unique aperture gate settings correspond to a unique combination of a position and a shape of said aperture gate (204a, 204b) in said aperture plane, analyzing (305) said plurality of images for generating data pertaining to a difference in stray light content with respect to said plurality of images, and producing (306) said output image based on said data pertaining tType: ApplicationFiled: April 24, 2014Publication date: October 30, 2014Applicant: Axis ABInventors: Jonas HJELMSTROM, Anders Johannesson
-
Patent number: 8848198Abstract: A method for determining a tilt of an image sensor surface plane in a camera in relation to a lens reference plane of the camera includes sending light onto the image sensor, receiving light reflected from the image sensor, identifying an interference pattern in the reflected light, identifying a feature of the interference pattern, and determining the tilt of the image sensor surface plane based on a position of the feature identified in the interference pattern.Type: GrantFiled: July 19, 2012Date of Patent: September 30, 2014Assignee: Axis ABInventors: Jonas Hjelmström, Anders Johannesson
-
Patent number: 8754975Abstract: A digital video camera performs a method to improve the image quality of captured images in a video image stream. The method includes capturing a first subset of images, outputting the images of the first subset of images as the video image stream, moving an image sensor and/or a lens of the digital video camera from a respective normal position to a respective test position before capturing an image of a second subset of images. The digital video camera captures a second subset of images interspersed with the first subset of images, compares image quality of the first subset of images with an image of the second subset of images, and determines if the image of the second subset of images exhibits improved image quality as compared with the image of the first subset of images. If so, an image quality improvement operation is initiated.Type: GrantFiled: December 13, 2011Date of Patent: June 17, 2014Assignee: Axis ABInventors: Jonas Hjelmstrom, Jan Sonnvik
-
Publication number: 20140002713Abstract: The present invention relates to a focusing device comprising: a lens, a lens plate, an image sensor, an image sensor plate, at least two rotatable structures, and at least two strips, wherein the lens is connected to the lens plate, the image sensor is connected to the image sensor plate, wherein each strip is arranged to be wound onto one of the rotatable structures, respectively, the rotatable structures and the strips are arranged between the lens plate and the image sensor plate, the rotatable structures and/or the strips are arranged in contact with the lens plate and the image sensor plate, and wherein a distance between the lens and the image sensor is adjusted by winding the strips onto or off the rotatable structures.Type: ApplicationFiled: March 18, 2013Publication date: January 2, 2014Applicant: AXIS ABInventor: Jonas HJELMSTROM