Patent Application
20050283987
The technical field of the application relates generally to measuring and aligning devices and specifically to laser measuring and aligning devices.
Alignment of surfaces is a perennial problem in a variety of fields, ranging from construction to interior decorating. Alignment is necessary for walls that should be perpendicular to a floor, or otherwise plumb. Masonry and brick-laying practitioners are well aware of the importance of plumbed and aligned surfaces and chalk lines. A home interior decorated with pictures and other wall ornamentation has a much better appearance when the ornamentation is aligned, especially with respect to vertical or horizontal alignment. Many mechanical and electrical alignment devices are available, including laser devices. Some of these products are cumbersome, others are not as useful as they could be. Chalk lines, for example, are undesirable for use in finished, interior areas.
Several aspects of alignment-product performance, and in particular of laser-alignment products, that could be improved are the width, brightness and straightness of the laser light. A visible, straight laser line may be limited in its brightness over a distance, and may also tend to defocus and become dimmer as a user works away from the source of the laser. Rotating lasers are used to project lines on walls perpendicular to the direction of propagation of the laser. Thus, such devices may have limited utility or may not work in confined spaces requiring a longer alignment tool.
Moreover, a conventional laser is not well-equipped for projecting a flat or planar beam of light. The essence of laser light is that it is coherent or substantially monochromatic, that is, of a single wavelength or a narrow wavelength band. Thus, when a beam of laser light is refracted through a prism, the prism output is not a spreading of the beam as with ordinary “white” light, but rather a coherent, focused beam, very similar to the input. The laser beam is thin and is only usefully visible when projected onto a surface.
Another aspect that could be improved is the inability of laser devices to work around obstructions. That is, if a wall-hanging, such as a picture frame, interrupts the laser beam, it may be blocked from further projection. Therefore, it is necessary to mark locations or heights, one by one, rather than working with the actual objects, in order to align them. Obstructions may include moldings placed in a doorway, picture frames in the way of those being aligned on one horizontal line, the operator of the device, other obstacles, or even textured or stuccoed surfaces on interior walls.
There are devices that direct a laser beam parallel to but away from a surface requiring alignment. A marker device or detector component is then used to sight the beam and mark corresponding locations on the wall adjacent the beam. Use of such a device requires multiple components and at least two people, one to align the laser and another to mark the wall.
Some laser devices attempt to use a laser light in combination with a reference surface, in order to place the laser light in the same plane with the reference surface. Thus, U.S. Pat. No. 5,604,987 incorporates a laser light in a carpenter's level, so that the laser light projects in the same plane as a surface of the level. However, this requires the level to have an interrupted surface, rather than a flat surface. An interrupted surface that is not flat cannot be used as a reference plane.
A conventional laser beam alignment tool is not able to project its laser light in the same plane as a surface of the alignment tool. It would be desirable to use a straight laser line or a planar beam of laser light in the same plane as a surface of the laser alignment tool.
One aspect of the invention is a laser reference device. The laser reference device includes a housing having a reference surface, a laser light generator mounted within the housing for generating laser light and projecting laser light outside the housing adjacent the reference surface. There is also an aiming device within the housing for adjusting a position of the laser light generator.
Another aspect of the invention is an aligning device. The aligning device includes a housing having two reference surfaces and a laser light generator mounted within the housing for generating laser light and projecting laser light outside the housing adjacent at least one of the reference surfaces. The device also includes an aiming device for adjusting a position or an angular orientation of a component of the laser light generator.
Another aspect of the invention is a method of making a laser aligning device. The method includes providing a housing having at least one planar surface, assembling a mirror into the housing, assembling a laser light source into the housing, and assembling an aiming device within the housing for aiming at least one of the mirror and the light source, wherein laser light reflected from the mirror leaves the aligning device adjacent the at least one planar surface.
Another aspect of the invention is a method of using a laser aligning device. The method includes placing the laser aligning device on a surface, and leveling at least one of the laser aligning device or the surface. The method also includes aiming the laser aligning device, and generating a beam of light adjacent a surface of the laser aligning device for aligning objects on another surface.
There are many ways to practice the present invention, as shown in the following drawings and specification. The embodiments are not meant to limit the invention, but rather to describe and illustrate a few of the many ways that the present invention may be used.
a is a top view of an embodiment of a light source and a lens;
b is a side view of the light source and lens of
c is a partial elevational view of a lens in a housing;
d is a top view of another lens embodiment;
e-2g are schematic views of further embodiments of aligning devices;
a and 3b depict an embodiment of an aligning tool projecting a fan-shaped beam of light onto nearby horizontal and vertical surfaces;
a is a schematic view of another embodiment of an aligning tool with two laser light sources projecting two perpendicular fan-shaped beams;
b is a side view of an application in which a horizontal fan-shaped beam is used to detect high points on a surface;
a is a top view of another embodiment of an aligning tool with a light source, and a lens projecting a fan-shaped beam adjacent to one surface;
b is a side view of another embodiment of an aligning tool with a light source, a cylindrical lens and a reflecting lens, projecting a fan-shaped laser beam along one surface;
a and 6b depict the comet effect of useful embodiments;
a-7c depict the divergence of the laser beam and compensation for divergence in embodiments of the present invention; and
Embodiments of the present invention overcome the above-mentioned difficulties and provide a virtual extension of a plane of a measuring or aligning device, by using a laser light that extends along an edge or flat surface of the measuring or aligning device. One embodiment of an aligning device according to the present invention is depicted in
Triangular aligning device 10 includes a housing 11, which may be made of molded plastic or metal, or other material that is suitably stiff and strong for use in alignment service. Housing 11 may include one or more bubble levels 12, preferably aligned parallel or perpendicular to the alignment surfaces 11a, 11b, of housing 11. The device may include a switch 13 for switching power from one or more batteries (not shown) to a laser light source. The switch may be a multi-position switch, enabling the user to turn on the desired light source, or to turn on or off each of the light sources.
The device may also include one or more on/off indicators 14, such as a light-emitting diode (LED), for indicating when the switch is in an ON position, enabling power from one or more batteries to reach the laser light source(s). When the power is on, laser light in the form of a fan 15a, 15b is projected adjacent to surfaces 11a, 11b of the aligning device. The light is virtually in the plane of surfaces 11a, 11b, allowing a user to virtually “project” an edge or surface of the device to a nearby wall or surface. Device 10 may also include a pencil 16, held onto the device with small grips 18, such as rubber or plastic grips, and may also include a pencil sharpener 17, machined, molded or assembled into the housing.
Aligning device 10 may be used by placing edge 11a or 11b flat onto a surface, such as a desk or a wall, and turning on a laser light source, enabling aligning device 10 to project light 15a or 15b, along an edge of surface 11a or 11b. The laser light may be in the shape of a fan-shaped beam, or alternatively, may also be in the shape of a line or “point” of light, rather than being spread into a fan shape. The “point” of light embodiment may allow the light to extend further, allowing the user to align objects many yards or meters away. Such embodiments will not shape the beam into a fan. The device may also be placed on its side, as shown, in
Aligning device 10 includes at least one lens 10a, 10b, for shaping light, preferably laser light, from a laser light source along at least one of the planar surfaces 11a, 11b of the aligning device. Housing 10 is designed so that at least one lens 10a, 10b is very close to the planar surface. The light emerges from the lens near the visible surface and propagates in the direction of the lens in the plane of surfaces 11a and 11b. The aligning device may also have set screws or other adjusting devices 10c for aiming the laser aligning device.
Aligning device embodiments according to the present invention may use one or more laser light sources and lenses to generate, collimate, and reflect laser light in the manner desired.
Optical device 23 may perform several functions, and may consist of several parts, such as a mirror or reflective surface 23a, a light pipe portion 22, a lens 24, and an exit surface 26. The configuration of optical device 23 and surface 23a may be such that total internal reflection results, with no light escaping except through exit surface 26. Lens 24 may convert the collimated laser light 21 into a fan-shaped beam. Light-pipe portion 22 transmits the reflected fan-shaped beam to lens 24 and exit surface 26, so that light beam 27 exits the optical device in a plane adjacent to reference surface 28. As the term is used here, an optical device may be any device used to transmit, reflect, focus or defocus light. A light pipe is any device that is used to transmit light, and may consist of any medium suitable for light transmission. The fan-shaped beam may subtend angle A as shown in
A laser source typically emits light in a generally ovate or elliptical form, with a major axis and a minor axis. A lens may convert the laser light into a fan-shaped beam. There are several lenses that will accomplish this, including at least one lens described in co-pending U.S. patent application 10/141,392, entitled “Laser Line Generating Device,” which is hereby incorporated by reference in its entirety. Laser light in a flat, fan-shaped beam 27 leaves optical device 23 and is directed outward parallel to reference surface 28. Lenses used in embodiments for generating a fan-shaped beam may be plano-concave, bi-concave, plano-convex, cylindrical, or of other suitable configuration, so long as the beam leaves in the desired shape, i.e., a fan-shaped beam or a focused laser “point.”
Aligning device 25 may also include devices 25a, 25b, for adjusting or aiming the laser source 20 and thus the direction of the light 27 emerging from laser source 20. Aligning devices shown include adjusting screws 25a and springs 25b. Any suitable and convenient adjusting devices may be used. For instance, with screws 25a, the angle of incidence θ2 of the laser light 21 onto mirror surface 23a may be adjusted, thus also adjusting the angle θ1 at which light is reflected from surface 23a and ultimately the angle of emergence from the optical device. This will adjust the direction of fan-shaped beam 27 as it leaves lens 26 and makes it possible to adjust or aim the beam. Adjusting devices may be used to adjust the mirror or the lens, or more than one of the laser source, the mirror and the lens.
b depicts a side view of laser light source 20 and lens with a mirror portion 22a and a lens portion 24a with a concave surface 26a. The concave surface converts the laser light into a flat, fan shaped beam. The divergence of the beam, represented by the angle A, is controlled by the lens. The plane of the beam may be adjacent and to the reference surface 28. As shown in darker lines in
One geometry that may minimize the difference between the bottom of the lens and the surface of the planar edge is depicted in
In other embodiments, an aligning device may simply reflect and bend a beam of laser light. As is well known to those skilled in the laser arts, laser light sources are available in which the light is emitted in a round or an elliptical shape. Thus, the aligning device may work with a light source that is either round or elliptically shaped. The lens may have a cylindrical component, or a concave or a convex component, that converts the laser light into a fan shaped beam. Alternatively, the aligning device may include only a mirror that directs the laser light along a plane adjacent to a reference surface. In other embodiments, the aligning device may have a separate mirror and lens for reflecting the light and then converting the light to a fan-shaped beam.
e through 2g are schematic views of other possible embodiments of aligning devices using different serial arrangements of components.
a-3b depict an aligning device with a single laser light source and lens placed on a horizontal surface, such as a table or work-bench, such that the light leaves the lens in a horizontal or vertical fan-shaped beam.
In
It will be understood that many other embodiments of aligning devices using the principles demonstrated in
The lenses used to focus and reflect laser light, and to generate a fan-shaped beam, are well known and need not be repeated here. For instance, cylindrical lenses are described in U.S. Pat. No. 3,854,820, U.S. Pat. No. 4,123,148, U.S. Pat. No. 4,901,207, U.S. Pat. No. 5,363,469 and U.S. Pat. No. 5,446,635, the disclosures of all of which are hereby incorporated by reference. These patents discuss a variety of lenses useful in reflecting light and in generating fan-shaped beams useful in aligning devices. Such lenses may also be useful in embodiments of the present invention.
a and 5b depict an embodiment in which a cylindrical lens 52 receives light 51 from a laser light source 50. Light leaves the cylindrical lens 52 as a fan-shaped beam 53 and is then reflected by a mirrored surface 55 of mirror 54. The light leaves as a fan shaped beam 56, and if mirror 54 is placed properly near the bottom surface of an aligning device, the fan-shaped beam may be virtually in the plane of surface 58 which holds the aligning device. Surface 58 may be a horizontal or vertical aligning device. Top view
One property of cylindrical lenses useful in aligning devices is that the light may emerge with a “comet effect,” in which the intensity of the light is greatest nearer one edge of the beam than the other. This effect is discussed in detail in U.S. Pat. No. 5,967,645, the entire contents of which are hereby incorporated by reference in their entirety. In aligning devices, the edge with the fainter light may be used on the “nearer” edge of the wall or surface on which alignment is desired, and the brighter light may be used on the “farther” edge of the wall. The comet effect arises because of the variation of intensity with the angle of incidence of the light with a surface.
The comet effect is depicted in
Aligning devices using light have contradictory requirements: the light intensity, as seen above in the discussion of the comet effect, diminishes with distance, while users wish for the aligning device to be useful at a considerable distance. This dichotomy is explored in
A more realistic situation is depicted in
The present invention helps to overcome this difficulty by aiming the aligning device using the aiming or adjusting features mentioned above with regard to
Another embodiment of an aligning device is depicted in
Aligning tool 80 includes a second laser alignment system 80b that also includes a laser light source 82, a second switch 89, and may include a lens 83b for converting the laser light into a planar beam. The light may then be reflected by optical device 84b, which may be a mirror or a lens or both. Thus, aligning tool 80 may use a planar beam 86 in one direction, and may use a single “point” of light 85 in another direction, which may be 180° from the direction of planar beam 86. One switch may be used in place of two switches if desired. Adjusting or aiming devices 81 a may be used to align one or more of the light source 82, lenses 83a, 83b, and optical devices 84a, 84b. These devices may include, among others, a set screw, a thumbscrew, a cam with a corresponding movement on the optical device, a spring, or any other suitable adjusting device.
It is intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention. It will be understood that no limitation of the scope of the invention is intended by the above description and drawings, which is defined by the claims below.
