WO2012013914A1

WO2012013914A1 - Portable hand-holdable digital camera with range finder

Info

Publication number: WO2012013914A1
Application number: PCT/GB2010/051249
Authority: WO
Inventors: Adam Lomas
Original assignee: Adam Lomas
Priority date: 2010-07-29
Filing date: 2010-07-29
Publication date: 2012-02-02

Abstract

A portable hand-holdable digital camera (10) comprises a camera housing (12) having a display (24), a power button (14), a shoot button (28), a flash unit (20), and a battery compartment; capture means (34) for capturing an image of an object in two dimensional form and for outputting the captured two-dimensional image to the display (24); first range finder means (46) including a zoomable lens unit (16) supported by the housing (12) for focusing on an object and calculation means (50) for calculating a first distance of the object from the lens unit (16) and thus a distance between points on the captured two-dimensional image viewed and selected on the display (24); and second range finder means (48) including an emitted-beam range finder (54) on the housing (12) for separately calculating a second distance of the object from the emitted-beam range finder 54, and for outputting the second distance to the calculation means (50) of the first range finder means (46) for combination therewith to improve distance determination accuracy.

Description

Portable Hand-Holdable Digital Camera With Range Finder

The present invention relates to a portable hand-holdable digital camera having a range finder for measuring dimensions of a photographed image.

It is known from JP2001004377 to provide a theodolite with a range finder. The theodolite can capture an image, and can utilise a range finder to determine a distance. However, a theodolite cannot be transported and operated easily by an architect at multiple job sites, and the range finder may produce inaccurate results. Furthermore, identification of edges and corners within a room or building is problematic, and determination of the length of selected edges cannot be undertaken. The present invention seeks to provide a solution to these problems, and which is particularly beneficial for architects when on-site.

In accordance with the present invention, there is provided a portable hand-holdable digital camera comprising : a camera housing having a display, a power button, a shoot button, a flash unit, and a battery compartment; capture means for capturing an image of an object in two dimensional form and for outputting the captured two-dimensional image to the display; first range finder means including a zoomable lens unit supported by the housing for focusing on an object and calculation means for calculating a first distance of the object from the lens unit and thus a distance between points on the captured two-dimensional image viewed and selected on the display; and second range finder means including an emitted-beam range finder on the housing for separately calculating a second distance of the object from the emitted-beam range finder, and for outputting the second distance to the calculation means of the first range finder means for combination therewith to improve distance determination accuracy.

An advantage of the invention is that manual measuring can be avoided and much time and energy can be saved. Another advantage is that the accuracy of the measurement can be increased by not only eliminating human error associated with manual measuring, but also by eliminating or reducing errors associated with a particular automated measurement system. A further advantage of the invention is that, since the camera is adapted for on-site use, and is designed to resist shock and be portable, there is less risk of damage to the camera due to transportation from place to place, dropping, banging, etc, compared with large and cumbersome sensitive measurement equipment. Preferable and/or optional features of the invention are set forth in claims 2 to 17, inclusive.

The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which :

Figure 1 shows a perspective rear or user's view of one embodiment of a portable hand-holdable digital camera, in accordance with the present invention;

Figure 2 shows a perspective front or objective view of the camera shown in Figure 1 ; and

Figure 3 is a generalised circuit diagram of the camera.

Referring to the drawings, there is shown one embodiment of a portable hand-holdable digital camera 10 which comprises a camera housing 12 having a power button 14 thereon, a zoomable lens unit 16 on a front or objective side 18 thereof, a flash unit 20 also on the objective side 18, a battery compartment 21 accessible preferably from a lower surface 22, and a display 24 on a rear or user side 26 of the housing 12.

A shoot button 28 for activating the unit once powered on, and a zoom button 30 for controlling a zoom of the lens unit 16 is also provided, in this case the user side 26 of the housing 12.

The lens unit 16 forms part of image capture means 34, which also includes an image capture circuit 36 within the housing 12 for outputting the captured image to the display 24 and/or to a fixed and/or removable data storage device. For example, at least one CCD 38 or CMOS array can be utilised as part of the image capture circuit 36. The lens unit 16, in this case, outputting the image to the CCD 38 or CMOS, which in turn is outputted as electrical signals to the display 24 and/or data storage device via appropriate image processing circuitry 40.

The display 24 is preferably touch-screen, and edge detection means 42 is provided within the housing 12 for processing an edge identification based on at least one input from the user on the touch-screen. To this end, the edge detection means 42 includes an image processing circuit 44 within the housing 12 and software for determining the edge of an image based on a user input to the touch-screen which identifies at least part of the edge on the displayed image.

To enable a distance measurement of an identified edge to be made, the camera 10 also includes first and second range finder means 46, 48 from which an average of the respective distance measurements is taken to provide a more accurate overall distance measurement used when determining edge length. The first range finder means 46 comprises the lens unit 16 and calculation means 50 in the form of a calculation circuit 52 for calculating a first distance of an object from the lens unit 16 and thus a distance between points on the captured two-dimensional image viewed and selected on the display 24. In this embodiment, the lens unit 16 is optically zoomable, and thus the calculation circuit 52 bases its calculation of the first distance on a focal length of the lens unit 16 electronically fed back from the lens unit 16 to the calculation circuit 52.

The second range finder means 48 includes an emitted-beam range finder unit 54 in the housing 12 for emitting a range finding beam. For example, the beam may be an infrared beam. The emitted-beam range finder unit 54 includes a separate calculation means 56, typically being a processing circuit 58 having calculation software, for separately calculating a second distance of the object from the emitted-beam range finder unit 54 based on a signal returned by the range finding beam. The calculated second distance determined by the emitted-beam range finder unit 54 is outputted to the calculation means 50 of the first range finder means 46 for combination therewith. An average is then taken to improve and/or optimise distance determination accuracy of the edge length or other points identified on the two-dimensional image on the display 24. The dimensioned image displayed on the display 24 may be savable with the dimension data intact on or adjacent to the selected edge and/or corner of the image and/or as a separate data file to the data storage device. This image showing the calculated improved or optimised dimensions, either identified via the edge detection means or manually if the edge detection means is dispensed with, can then be uploaded to a computer or other peripheral device for further analysis and/or printing, for example, on a larger scale.

Preferably, the camera 10 also includes a mode button 60 wherein it can be used in a first mode as a regular camera, and in a separate mode wherein it is used to measure dimensions of a space. The mode button 60 may be assigned to switch between camera and dimension mode, or the mode may be selected via menus or other multiple-use buttons. The camera 10 can preferably take measurements in metric and/or imperial units.

Although the zoom capability of the camera 10 is optical, it may additionally or alternatively be digital. In this case, the first range finder means 46 may utilize pixilation of the image to determine distance, instead of or in addition to focal length. There are two advantages to zooming into an image of a space. Firstly, using optical or digital zoom the user can select more precisely on the screen the point in the image that is required to be measured. Secondly, using optical zoom the camera 10 can focus more precisely and therefore take a more precise measurement of the distance to the object or space.

The camera 10 is adapted for on-site use, for example by surveyors, estate agents, builders, site managers, engineers, and the like, and therefore comprises features to adapt it for this use. Beneficially, the camera 10 is at least coat-pocket sized and more preferably trouser-pocket sized so that it can be easily carried, stored and transported.

The camera 10 has a touch-sensitive display screen 62 and preferably a stylus for touching the screen. For a camera 10 of the invention preferably equipped with edge- detection technology as described above, a user can use the stylus to select the elements of the image, and therefore the elements of the object or space, which he wishes to measure. This can be a point, line, area or volume. Without edge detection technology, the stylus can still be used, albeit with less ease, to delineate points, lines, areas and volumes manually. The use of the touch-sensitive screen 62 and stylus increases the speed at which the camera 10 can be used to obtain measurements, thereby adapting it for quick, ready, on-site use. Furthermore, the stylus preferably slots into a stylus compartment or hole built into the housing 12 of the camera 10 for compactness and safety, which further adapts it for on-site use. Mechanisms known in the art for securing and removing said stylus such as click mechanisms or slide mechanisms may be used.

Preferably, a graphical user interface (GUI) provides intuitive instructions on how to select and measure points, lines, areas, volumes and the like. The GUI may display on the touch-screen display 24 an image of a space with highlighted lines and shapes, selected line, and a measurement which is determined by the combined first and second distance measurements. Preferably, in different modes, the stylus can be used to select points, lines, areas or volumes using edge detection technology, and the GUI can display their measurements, relative distances, etc, on-screen. An advantage of this feature is that measurements can be read by a user on-site and there is no need to download the images to a computer in a remote location to read the measurements. Furthermore, this makes the camera 10 user- friendly and intuitive, and therefore easier to use in an on-site location where conditions may not be favourable. Alternatively, there may not be a graphical user interface and other means known in the art may be used to operate the camera 10 of the invention.

The camera 10 is preferably designed to resist shock upon dropping or banging, and preferably comprises at least one protective molding 64 on at least one side of the housing 12 for this purpose. More preferably, protective moldings 64 cover each corner of the camera 10 for increased protection. Preferably, rubber is used for the moldings. Alternatively, other natural or synthetic shock-absorbing materials, such as plastics, may be used. Thus there is less risk of damage to the camera 10 due to transportation from place to place, dropping, banging, etc, compared with similar sensitive and accurate photography and measurement equipment. The housing 12 also preferably comprises a lanyard connector 66 for connecting a lanyard and wearing around the neck. An advantage of this is that the camera 10 is less likely to be dropped when being worn around the neck. Furthermore, this frees up both hands for climbing ladders and otherwise navigating around a site which may be partially built and otherwise awkward to navigate.

The camera 10 is beneficially used for obtaining measurements of a space by capturing a two dimensional image and calculating measurements of said space based on said image. The dimensioned image is displayed on the display 24, so that the calculated dimensions can be viewed on the or adjacent to the parts measured. The camera is adapted to store the dimensioned image to allow outputting and remote display and printing of the image with the dimensions on or adjacent to the parts measured. The camera 10 is adapted for on-site use by being ruggedized and compact, thus dispensing with the need for a tripod and other theodolite apparatus. The invention can be used in a method for quickly obtaining measurements of a space, comprising the steps of: capturing a two dimensional image of said space; and estimating the dimensions of said space from said image using an average of two separate distance measurement means. Preferably, the method uses the camera 10 of the present invention.

The term 'space' is used in the present application to mean any place, area, volume, etc which can be photographed. The invention is directed towards taking measurements of the inside or outside of a building, and the space may be a room or part of a room inside a building or a part or whole of the outside of a building. However, the space may be any area of which an image can be taken. The space may be a very large area such as an entire landscape several miles wide or may be a very small space of the order of a few cubic metres or centimetres in volume. The term On-site' is used herein and throughout to mean at the location where the image is captured thus enabling measurements to be taken while the user remains at the 'space' where the image was taken. The invention is directed towards use by surveyors, estate agents, builders, site managers, engineers, and the like, therefore 'on-site' is most likely to be a building site, a demolition site, an industrial or residential building or outdoor location and is therefore likely to be a place which is hazardous and awkward to navigate. The term On-site' may however be used to refer to any location where an image is captured.

The camera 10 is preferably a digital camera 10. An advantage of this is that images can be more readily accessed by on-board software for dimension estimation. Preferably the camera 10 includes at least one USB port, Bluetooth RTM and/or other wireless connectivity protocol, removable rechargeable battery, tripod adaptor provided on a lower surface 22 of the housing 12, and memory card slot or slots. The camera 10 may have one, more or a combination of these features.

The calculation means for calculating measurements of said space based on said image are image-based object reconstruction techniques. Very broadly speaking, the means for calculating measurements of said space preferably operates along the following principles. Preferably, the means for calculating measurements of said space comprises a lens and software for focusing the lens on an object within the space. In focusing the lens, the software calculates the distance from the camera to the object based at least primarily on focal length. This distance is then used to calculate approximate values of the other distances within the image in light of angular spacing, focal change, and the preferable edge recognition technology. Using the calculated distance from the camera to the object, the software scales up the distance between points on the image to create an estimate of the distances between points on the object or within the space. The emitted-beam range finder generates a distance based on, for example, the reflected light. This is compared to the distance determined using the focal length of the first range finder means, and a base distance is thus determined. This correction value is then utilized to moderate the other off- focus values, whereby a more accurate distance can be determined between the points. Further techniques are known in the art for edge detection, and preferably these are also included in the camera. Using such technology, when in dimension mode the camera can detect edges, corners, areas and the like and automatically highlight them on-screen. The user can then easily select a corner, wall, floor, or other surface or line that is required to be measured, simply by selecting a point on the surface or line and without having to accurately delineate it using a stylus or other method. Specifically, the camera preferably comprises as part of the second range finder means an infra-red or laser range finder for calculating the distance between the camera and the object in the space. This range finder provides a second estimate of the distance which can be combined with the first as estimated by the lens and software to increase accuracy.

It may be feasible to provide a further separate different range finder for further optimizing a calculated distance. For example, if a focal length range finder and an infra-red range finder are provided, then a laser range finder may also be incorporated into the camera.

The embodiments described above are provided by way of examples only, and various other modifications will be apparent to persons skilled in the art without departing from the scope of the invention as defined by the appended claims.

Claims

1. A portable hand-holdable digital camera (10) comprising : a camera housing (12) having a display (24), a power button (14), a shoot button (28), a flash unit (20), and a battery compartment;

5 capture means for capturing an image of an object in two dimensional form and for outputting the captured two-dimensional image to the display (24); first range finder means (46) including a zoomable lens unit (16) supported by the housing (12) for focusing on an object and calculation means (50) for calculating a first distance of the object from the lens unit (16) and thus a distance between points on o the captured two-dimensional image viewed and selected on the display (24); and second range finder means (48) including an emitted-beam range finder on the housing (12) for separately calculating a second distance of the object from the emitted- beam range finder, and for outputting the second distance to the calculation means (50) of the first range finder means (46) for combination therewith to improve distance 5 determination accuracy.

2. A portable hand-holdable digital camera (10) as claimed in claim 1, wherein the emitted-beam range finder includes an infra-red emitter.

3. A portable hand-holdable digital camera (10) as claimed in claim 1 or claim 2, further comprising edge detection means (42) for in use automatically detecting selected 0 edges and/or corners of portions within the displayed captured two-dimensional image, the first range finder means (46) and/or the second range finder means (48) determining a distance of a said selected edge and/or to a said selected corner.

4. A portable hand-holdable digital camera (10) as claimed in claim 3, wherein in use an improved distance calculated from the first and second distances is displayable5 on or adjacent to the selected edge and/or corner of the image on the display (24).

5. A portable hand-holdable digital camera (10) as claimed in claim 4, wherein the said displayed image with selected edge and/or corner and displayed improved distance is savable to a data storage device and/or is outputtable via an output port to a remote device.

6. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising camera/dimension mode selector for manually selecting between a camera (10) only mode in which the first and second distances of the first and second range finder means (46, 48) are not calculated, and a dimension measuring mode in which the first and second distances of the first and second range finder means (46, 48) are calculated.

7. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising a removable data storage device port for connection with a removable memory card device.

8. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, wherein the lens unit (16) is optically zoomable and the first distance is calculated based on a focal point.

9. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, wherein the lens unit (16) is digitally zoomable and the first distance is calculated based on a pixilation of the image displayed on the display (24).

10. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, wherein the display (24) is a touch-screen.

11. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, wherein the calculation means (50) is software-based.

12. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising a stylus for touching said screen.

13. A portable hand-holdable digital camera (10) as claimed in claim 12, further comprising a stylus compartment for storing said stylus compactly.

14. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising a graphic user interface adapted to measure and read measurements.

15. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising a lanyard connector (66).

16. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising at least one protective molding (64) provided on the camera housing (12).

17. A portable hand-holdable digital camera (10) as claimed in any one of the preceding claims, further comprising wireless data transfer means for transferring data to and from the camera (10).