(1) Field of the Invention
This invention relates generally to lighting systems and relates more specifically to dynamic lighting systems in which the animated element is steered by a magnetic field.
(2) Description of the Prior Art
Lighting applications require an increasing amount of dynamic lighting systems. The reason for this development is partly due to the increasing flexibility of working areas and living quarters and partly because of a rising demand for situational lighting scenes. From a technological point of view, the development of LED (white and colored) has supported and fostered the demand for alterable light.
The light direction, light distribution, color distribution and the stability of the light all play a big role in the application. Rigid systems only cover particular illumination functions and must therefore be adjusted manually to comply with changing demands.
Familiar dynamic lighting systems are those whose optics can be set using a motor and transmission (e.g. US 2002/0036908A1—LED warning signal light and moveable row of LED's). This solution has the considerable drawback that the mechanical parts used in the system have more wear and tear, which has a negative effect on the operational life span. In addition, these systems are rather sluggish and cannot react quickly to fast changes.
Known systems based on motor-transmission elements can also get jammed when there are fluctuations in the temperature. Because modern lighting systems based on LED technology are exposed to temperature stress, an innovative solution is required offering significant advantages in relation to sturdiness when exposed to stress caused by temperature changes. As a result, mechanical tension in the lighting systems is avoided.
It is a challenge to accomplish a dynamic lighting system having an extended life span, allowing moving parts to be easily positioned and re-positioned while the different positions can be progressively taken and appointed.
Solutions dealing with lighting systems are described in the following patents:
U.S. Patent (U.S. Pat. No. 7,220,029 to Bynum et al.) teaches a lighting assembly being adjustable between flood and spot lighting conditions for selectively illuminating an interior passenger compartment in a motor vehicle. The assembly includes a housing, which clamps to a supporting member, such as a headliner, via a sleeve interacting with a rotary cam lock. An LED light source is orbitally supported within the housing for projecting light in a directionally adjustable manner. A lens is disposed in the light path and is moveable between an extended spot position for task lighting and a retracted flood position for general illumination within the interior compartment. A switch is responsive to movement of the lens into its spot position for automatically energizing the LED. The switch opens, thus de-energizing the LED when the lens is returned to its flood condition. A lighting control circuit is responsive to an override signal, such as from a door switch, for independently activating the light source when the lens is in its flood position. The light source is supported for orbital movement within the housing by a gimbal mechanism, which includes an inner gimbal carried in a cross. Pintles establish intersecting perpendicular axis to accomplish the orbital movement.
U.S. Patent Publication (US 2008/0198617 to Schwab et al.) discloses an LED adaptive forward lighting system for an automotive vehicle comprising a headlamp housing fixed to the vehicle for mounting LED lamp units having fixed light beam directions. The LED lamp units each have mounting pivots and link pivots that are spaced from one another to provide lever arms. The mounting pivots mount the LED lamp units on a bezel within the housing.
U.S. Patent Publication (US 2008/0266856 to Chien) describes a light device with changeable function which at least one of any conventional available light means install within housing-unit or joint-means and the said housing-unit and joint-means can be change the orientation, or position, or viewing angle, or others light properties related to any other of the said light means to allow the said light device emit light beam to desired direction to make illumination to viewer. The said light device selected incorporated with solar means, wind generator or other generators, home electricity to get the power to turn on the said preferred light means under predetermined functions.
U.S. Patent (U.S. Pat. No. 6,305,830 to Zwick et al.) teaches lighting optics for lights of vehicles, preferably motor vehicles. The lighting optics has a light-refracting lens element that is disposed in the path of rays of at least one light. The lens element has at least one aperture through which a portion of the rays of the light passes without undergoing refraction.
U.S. Patent (U.S. Pat. No. 5,151,580 to Metlitsky et al.) discloses a portable scanning head emitting and receiving light from a light-emitting diode to read symbols, such as bar-code symbols. The optics within the scanner is operative for focusing a light beam and the view of a light sensor in different planes exteriorly of a scanner housing. Imaging means are provided in the unit for imaging a viewing window. The viewing window has an area smaller than that of the scan spot. The system can employ an LED as a light source and tolerate the relatively large-sized (on the order of millimeters) scan spot without sacrificing reading performance since the photodiode “sees” only that portion of the scan spot visible through the viewing window.
A principal object of the present invention is to achieve a dynamic lighting system having an extended life span.
Another principal object of the present invention is to achieve a dynamic lighting system having minimal mechanical wear.
Another principal object of the present invention is to achieve a dynamic lighting system having reduced mechanical dimensions.
Another principal object of the present invention is to achieve a dynamic lighting system having minimized movable mass.
Another principal object of the present invention is to achieve a dynamic lighting system having minimized energy demand for dynamization.
Another principal object of the present invention is to achieve a dynamic lighting system wherein the position of the moving element(s) can be continuously varied.
A further object of the present invention is to achieve a dynamic lighting system reacting quickly to fast changes.
A further object of the present invention is to achieve a dynamic lighting system being not sensitive to temperature fluctuations.
A further object of the present invention is to achieve a dynamic lighting system wherein movable elements are steered by a magnetic field.
A further object of the present invention is to achieve a dynamic lighting system wherein positions of movable elements can be progressively taken and appointed.
A further object of the present invention is to achieve a dynamic lighting system wherein moving parts can be positioned linearly, two-dimensionally or three-dimensionally.
In accordance with the objects of this invention a method for dynamic lighting systems avoiding mechanical tension enabled having utmost flexible positioning, has been achieved. The method invented comprises the following steps: (1) providing at least one light source, one or more movable optical elements (could be) to guide light from the at least one light source, a control module, and means of power transmission to move the optical elements to position desired up to three dimensions, wherein the optical elements could be e.g. lenses, mirrors, fiber optics, prisms, variable lenses, etc. (2) deploying a magnetic power transmission to move said optical elements, and (3) controlling said power transmission by said control module. Optionally the actual positions of the one or more movable optical elements are sensed and fed to the control module in a control loop.
In accordance with the objects of this invention a dynamic lighting system has been achieved. The lighting system invented firstly comprises: at least one light source, and at least one movable optical element guiding light from said at least one light source. Furthermore the lighting system comprises a power transmission changing a position of said at least one movable optical element by a controlled magnetic field, and means of bearing being connected to a static element of the lighting system guiding said at least one movable optical element.
In the accompanying drawings forming a material part of this description, there is shown:
a prior art shows an application of a lighting system, e.g. a prior art street light providing light on an ellipsoid area of a street.
b shows as example an embodiment of the present invention It shows a street light using the present invention having a dynamic light distribution curve, covering a much larger lighted area, but only where required, than the area covered by prior art. The improvement shown here is related to reduce “wasted light” outside the street. The light distribution follows the course of the street.
a illustrates the basic idea of the present invention. It shows an oblique view of the lighting system invented.
b shows a side view of the lighting system of the present invention, wherein the x-y table 41 is guided by balls 42 of ball bearings.
a-c show principles of function of a first embodiment of a power transmission used with the present invention.
d-f shows the function principles of a second embodiment of a power transmission used with the present invention.
a-c illustrate how the inductances of coils vary dependent on the positions of the moving part of the motor, i.e. the positions of the permanent magnets.
a-c illustrate similarly how the inductance of coils vary dependent on the position of the moving part of the motor, i.e. the positions of the permanent magnet moving inside of the coils.
a-c illustrate Alvarez lens technology comprising two optical elements (lenses) that can be used to generate different light distributions.
a-f show schematic functions of Alvarez- or Lohmann (alternative solution to the Alvarez lens) lens systems.
a-c show how the optical properties of a fluid-filled lens can be changed by changing the amount of fluid of the lens.
Systems and methods for dynamic lighting systems having minimal mechanical wear and reacting quickly to fast changes by using magnetic power transmission moving optical elements between light sources have been invented.
The present invention discloses systems and methods in which one or more animated elements (e.g. the optics) are steered by a magnetic field, i.e. a linear motor. The moving part lies over e.g. a ball bearing. This type of system reduces the vulnerable mechanics (transmission) and is liable to much less mechanical sluggishness. The magnetic power transmission allows the moving parts to be positioned and in addition a position that was already appointed can be re-appointed.
a prior art shows an application of a lighting system, e.g. a prior art streetlight 1 providing light on an ellipsoid area 2 of a street 3.
b shows as example an embodiment of the present invention. It shows a streetlight 4 using the present invention having a dynamic light distribution curve. The improvement shown here is related to reduce “wasted light” outside the street. The light distribution follows the course of the street covering a much larger lighted area 5 and only where required than the area 2 covered by prior art shown in
a shows the function principles of a first embodiment of a power transmission used with the present invention. It shows two coils A and B wrapped around a fixed iron 100. Two permanent magnets 102 are deployed building each a magnetic field towards the coils/iron combination. The directions of currents through the coils A and B are indicated by either dots or crosses generating a magnetic field either upwards to the permanent magnet or downward to a coil dependent upon the direction of the currents.
d shows the function principles of a second embodiment of a power transmission used with the present invention. A permanent magnet 104 is moving between two coils A and B.
a+b illustrate how the inductances L1 and L2, i.e. of coils A and B in
a-c illustrate, according of the embodiment of the linear motor shown in
It should be noted that alternatively to the position sensing integrated in the linear actuator described above, the position of optical elements could be determined by capacitive sensors or by Hall sensors. Only one coil can be deployed alternatively to generate the power transmission to the movable parts.
It should be noted that one control IC could control multiple actuators. In a preferred embodiment of the present invention a control IC does control all actuators used as well as one or more LEDs, wherein other light sources are applicable as well.
Another advantage of the present invention on hand is that the positions are variable and can be progressively taken and appointed. Therefore using a linear motor with integrated position sensing can be used advantageously. Known systems with, for example, stepper motors, can only take a position “step by step”. This effect works at a disadvantage to visual systems because light distribution needs the most continuous procedure and positioning of the, for example, optical elements, possible. Otherwise the lighting changes would be erratic and/or the optical elements wouldn't be able to be used completely in their resolution.
The moving parts can be positioned linearly, two dimensionally in an x, y direction, or three dimensionally (x, y, z). Through the various positions of the optical element in relation to the light source, a number of different light distributions or illuminations on illuminated objects can be produced.
It should be noted that for each direction, e.g. three directions, a linear motor could be deployed to modify light distribution. Alternatively along the optical axis, light distribution can be modified by one or more variable lenses. Such a lens can be made of a transparent, flexible plastic container filled with water or another fluid. Another benefit is that the water itself can be used for cooling.
a-c show how the optical properties of a fluid-filled lens can be changed by changing the amount of fluid of the lens. The amount of fluid can be modified by a pump and the pumped fluid changes the shape of the lens and hence the light distribution.
Alvarez and Lohmann lenses are variable focus optical devices based on lateral shifts of two lenses with cubic-type surfaces. These kinds of lenses can be used to modify light distribution.
a-c illustrate Alvarez lens technology comprising two optical elements (lenses) that can be used to generate different light distributions. The movement of one or more optical elements with different shapes changes the light distribution. The shapes could form a complete optical element or be based on micro-structures in which multiple micro Alvarez lenses are integrated on optical elements.
a-c show how a Alvarez lens changes its focus by laterally moving either the upper or lower lens component or both lens components.
a-f show schematic functions of Alvarez- or Lohmann (alternative solution to the Alvarez lens) lens systems. A light source 160 generates a light beam 161 through the variable lens comprising a first 162 and a second part 163, wherein the relative positions of both parts can be changed by moving either one or two parts of the lens. Outer cubic surfaces configuration at: (a) neutral position, (b) negative power addition, and (c) positive power addition. Inner cubic surfaces configuration at: (d) neutral position, (e) negative power addition, and (f) positive power addition. For the outer cubic surfaces configuration there must be a space between both lenses to avoid collision when the shift is done to achieve positive power addition (f).
The present invention can also provide that, dependent upon the position, the brightness of the spot light source (ideally one or more LEDs) can be changed. At the same time flexible light intensity depending on the angle can be achieved. Another embodiment of the invention steers various LEDs (e.g. in different colours) dependent upon the angle position.
a illustrates a basic idea of the present invention. It shows an oblique view of the lighting system invented. A movable primary optical element (deflector) 32 is moved across a light source 30. A movable x-y table 41 carries the movable optical element 32. The x-y table 41 is moved by power transmission (not shown) to a position desired as described above and is guided by a bearing, which can be e.g. a plain bearing or a ball bearings. A control module 43 controls the power transmission to move the movable optical elements and the light source 30, e.g. a LED. In some embodiments of the present invention the control module 43 controls more than one light source.
b shows a side view of the lighting system of the present invention, wherein the x-y table 41 is guided by balls 42 of ball bearings.
It is also possible to revolve optical elements around their own axis in a wobbling motion. In this case in a preferred embodiment the optical element is hung with springs. Furthermore it should be noted that any kind of movement, including tilting, of one or more optical elements could be realized with the present invention and changing of positions of one or more optical elements includes tilting.
Other types of light sources could be used as well.
Another embodiment of the invention is characterized by a link of the position with external control signals. The steering information can be taken from various sources depending on the application such as:
#Manual control element for adjusting the position
# Motion detector
# Vibration sensors and tilt sensors
# Curve pathways of moved objects
# Brightness sensors
# Heat sensors (Infrared)
# Software programmes (processes, timing)
# Mobile devices (Cell phones, PDA's)
# Solar devices including the positions of the sun
It should be understood that the signals above are non-limiting examples. Other signals are possible as well with the present invention.
The results of the example of the signals shown above are the following adjustable parameters of the light delivered:
# Light cone (small beam width, large beam width)
# Light direction (angles of the optical axis)
# Light distribution (shape, symmetric, asymmetric)
# Intensity distribution and color distribution
Other lighting effects can be achieved as well. The steering of the light sources, e.g. of LED, OLED, etc., in dependence upon the positions of the movable optical elements is variable. It can be modified any time or synchronized and variously colored light sources can be accessed upon the positions of the optical elements.
The light guidance occurs through shifting the relative position between the light-giving source and one or more optical elements. In the course of this the movement can be either straight (x, y, or z) or it can be conducted onto a spherical course. The effect of the light guidance can be increased by using one or more light sources having narrow light distribution (e.g. 10°) or a collimator so that the primary emission is closely focussed on the delivering light source or light collimating (collimated light is light whose rays are nearly parallel) is carried out. A special embodiment pertains to the use of light mixing optics that collimate at the same time and the light is ultimately diverted over an animated visual effect.
Because the present invention doesn't require a solid mechanical, linked system between the rigid and the moving parts, an exact mechanical positioning of the moving parts is not used purely through the setting adjustments. The invention provides for determining the position over the same magnetic pathway that is used for power transmission in that a test current is laid on the magnet coil and the induction potential is measured as disclosed e.g. in the patent application DI08-004, titled “Camera Shutter”, Ser. No. 12/658,508, filing date Feb. 5, 2010, and in the patent application DI09-007, titled “Twin-actuator configuration for a camera module”, Ser. No. ______, filing date ______.
Thus it is possible to determine the exact position of the moved part or parts. Beside the static adjustment of a particular position and the subsequent particular light guidance, the invention also provides for the moved parts to be moved dynamically at a certain frequency. Depending on the size and mass of the part that is to be moved, it can take place either directly or indirectly; for example over a smaller inter-optic with less mass. Through the movement of the optics with higher frequencies (over 100 Hz) effects can be achieved as e.g. adjustments to light distribution curves and optical diffusers with high efficiency.
Light systems based on LED technology still have a lot of problems when it comes to high temperature development. The high delivery power on the LED chip causes a power loss that has to be discharged thermically over the LED system in order not to exceed the temperature limits of the LEDs. The present invention opens the possibility of combining the dynamic behaviour of the optics with the cooling of the LEDs. Through the cyclic process, airflows can be created in connection with the mechanical housing that can be used to cool the LEDs and the LED system. If a specific visual effect position is static, the optics can be made to vibrate through small displacements that create airflow and in consequence, cool the LED system. It is also possible to shift the optic elements around a fixed working point and get the vibrations.
The present invention also takes into account that OLED foils change their shape and position. The power transmission affects the OLED foils and deforms them by, for example pushing them together. In this way, new light distribution characteristics are created. The basis technology stays the same as for the LED application.
Furthermore it should be noted that a mechanical brake or lock could be applied to the moving parts when their movements are switched off. Moreover a home position can be defined for the moving parts whereto they return if the lighting system is switched off.
Furthermore a calibrating routine can be activated when the lighting system is switched on in order to determine the exact positions of the one or more movable parts. The impact points of the power transmission are thus navigated and the related data is evaluated electronically.
It should be understood that different types of light sources could also be used with the present invention. In preferred embodiments of the present invention LED or optionally OLEDS have been deployed. Alternatively all light sources that deliver a point light could be used as well as e.g. miniaturized discharge lamps.
In the following sections are some non-limiting examples of applications of the present invention described:
In this area of application a change of the light according to the situation is desired. For example in the case of a “task light” it may be required that the entire table area be illuminated, whereby in the case of a reading task, the light should be focussed mainly on the reading area. Steering the light for both lighting tasks could be done by keeping the light intensity at one level—like the surface of the table—at a constant. In this way the smaller light cones save energy because the electric output is reduced.
Incandescent light bulbs are banned legally in many countries. Alternative lamps are needed for the market. Lamps based on LEDs are a preferred option and multiple products are available. Light Bulbs based on this invention will have the opportunity to change the light direction, shape of light distribution. Different operation mode may be changed by a switch integrated in the bulb or by pressing the mains switch multiple times or by wireless/remote commands (e.g. IR) or by a phase cutting dimmer.
With pathway lighting there is the requirement that not only the pathway itself has a specific minimum light intensity but also that a maximum ratio of minimal to maximum light intensity must not be exceeded. Both of these requirements can be adapted with the present invention. Because the light intensity can be changed dependent upon the angle of illumination, the light distribution curve can be adjusted to the desired shape and intensity distribution. In this way, for example, curves can be illuminated correctly and the distance from lamp to lamp can be increased by a homogeneous light, which in turn reduces the investment costs of the lighting system.
Homogeneousness is also required with emergency lighting equipment on escape routes. Classic lighting systems have less light intensity at the edge of the illumination light cone than in the centre of the lamps. This present invention can greatly improve the homogeneousness through dynamic control of the lighting dependent upon the illumination angle. The energization of the light sources is increased at the edges of the radiated lighting and with that the illumination is increased.
Bending light is a well-known application of flexibly steered light. The present invention makes it possible to carry out fast changes in light control. With this, it is possible to compensate for the automobile's vibrations and to stabilize the light when the vehicle is moving. Tilt information makes it possible to adapt the horizontal illumination angle so that glare effects from oncoming vehicles is avoided. The car headlights of the present invention can also be curve lights, i.e. a curve light angle is determined by the car's speed and steering angle, which can be analyzed by sensors.
The task in this application is, for example, to track a person e.g. on the stage around with the light. Using position detection, the light can track a moving object automatically. Manual steering is known and this can also be covered by the present invention. The advantage here is a quick response time.
The technology presented here makes new applications in the area of accent lighting possible. Especially the fact that in dependence upon the optical deflection, various light intensities and colours can be steered which allows for the depiction of, for example, a rainbow colour effect on walls with one single lighting system.
Another kinds of applications for the described technology are beamer applications whereby a miniaturized application of the present invention is assumed. Through joint circuiting of a number of systems that are based on the invention, light overlays can be achieved in an array that creates a colour blend on a depictive surface. By using various colors, color pictures can be projected on surfaces.
It should be noted that the control of the moving optical elements ensures that the illumination of moved objects is stabilized, whereby tilt or vibration information is fed for the compensation of the moved object. This stabilization could be applied for e.g. track lights on boats, searchlights, car lights, etc.
A second pair of coils 183 each wrapped around an iron generates a magnetic field moving each a permanent magnet 184 in y-direction, wherein the magnet 184 is firmly connected to a y-table 185. The y-table 185 is guided by balls of a ball bearing moving in y-direction.
The optical axis, i.e. the direction of light, of the lighting system shown in
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.
This application is related to the following US patent applications: DI08-004, titled “Camera Shutter”, Ser. No. 12/658,508, filing date Feb. 5, 2010, and DI09-007, titled “Twin-actuator configuration for a camera module”, Ser. No. ______, filing date ______, and the above applications are herein incorporated by reference in their entirety.