The present application claims priority to European patent application titled, “ILLUMINATION DEVICE WITH UNIFORM LIGHT BEAMS,” filed on Jun. 12, 2014 and having Application No. 14 172 100.1. The subject matter of this related application is hereby incorporated herein by reference.
The present invention relates to an illumination device with light beams.
Illumination devices or light fixtures creating different light effects are used in different fields of application, inter alia in the entertainment industry or as part of an architectural installation.
Illumination devices can generate a light beam having a certain beam width and a certain divergence and can inter alia generate a light beam with a uniform light distribution. Furthermore, the illumination devices may be adapted to project an image onto a target surface. Recently, LEDs (light emitting diodes) have replaced the former light sources in the illumination devices. Multiple LEDs emitting different colours often replace a single light source. This, however, changes the visible appearance of the illumination device, as the multiple LED light sources are exposed to the viewer and the light emits from a larger area. If single colour LEDs are used in a colour mixing version to generate a colour, then all the LED colours might be visible. However, the appearance of multiple light dots may be not satisfying.
WO 2011/131197 discloses an illumination device with a first group of light sources which illuminate different optical lenses to which for each optical lens a light beam is generated. Furthermore, a second group of light sources is provided generating a background light for the parts of the illumination device between the optical lenses. A need exists to further increase the flexibility when generating light beams in an illumination device.
This need is met by the features of the independent claims. The dependent claims describe further embodiments.
According to a first aspect, an illumination device is provided comprising a group of first light sources and a plurality of optical lenses. Furthermore, a plurality of beam generating elements are provided wherein each of the beam generating elements is configured to collect the light of at least one first light source and is furthermore configured to generate a light beam of the collected light. Furthermore, the beam generating element is configured to pass the generated light beam to one of the optical lenses. The illumination device furthermore comprises a group of second light sources and a plurality of shielding elements. Each shielding element is arranged between at least one of the second light sources and one of the plurality of optical lenses in such a way that said at least one of the second light sources illuminates only one of the plurality of optical lenses. In other words, each shielding element is arranged such that it prevents the light emitted by said at least one second light source to illuminate another than said one optical lens so that the light of each of the second light sources illuminates one of the plurality of optical lenses.
This illumination device has the first light sources with which the optical lenses can be illuminated and with the result that a plurality of light beams exist at the optical lenses. With the use of the shielding elements, the second light sources can also be used to illuminate the optical lenses. As the beam generated by the first light sources may be different from the light beam generated by the second light sources and the corresponding shielding element, the illumination device can generate light beams of a variety of shapes so that in total the flexibility in generating light beams is increased. In addition, the second light sources can be configured to illuminate the optical lenses without generating light beams and the front surface of the illumination device can as a result provide a graphical display where the optical lenses act as pixels without generating a light beam.
Details of the invention and further embodiments will become apparent from the following detailed description.
The present invention relates to an illumination device designed as described in a moving head lighting fixture including a number of LEDs that generate a light beam, however the person skilled in the art realizes that the present invention relates to illumination devices using any kind of light source such as discharge lamps, OLEDs, PLEDs, plasma sources, halogen sources, fluorescent light sources, etc. and/or combinations thereof. It is to be understood that the illustrated embodiments are simplified and illustrate the principles of the present invention rather than showing an exact embodiment. The skilled person will thus understand that the present invention can be embodied in many different ways and also comprise further components in addition to the shown components. The illumination device can comprise a group of first light sources, a plurality of optical lenses, beam generating elements, and a group of second light sources. Furthermore, shielding elements are provided guiding the light from the second light sources to one of the optical lenses.
The illumination device may furthermore comprise a plurality of diffusing elements wherein each of the diffusing elements is arranged between at least one second light source and the corresponding optical lens such that the light emitted by said at least one second light source passes one of the diffusing elements before passing the corresponding optical lens.
When the light emitted by the second light sources passes through a diffusing element before passing the optical lens, the light is further diffused so that a less focused light beam compared to the light beam generated by the first light sources is generated. With the diffusion elements, a more homogenous, wider light beam can be generated that passes one of the optical lenses. Furthermore, with the diffusing elements, the single light dots generated by the second light sources are less visible to a viewer so that a more uniform even light is generated. In addition, the diffusing element can also assist in creating a homogenous illumination of the optical lenses by light from the second light sources resulting in the effect that each of the front lenses appears as single homogenous light beam.
The diffusing element can contain an aperture wherein one of the beam generating elements passes through the aperture. The group of first light sources can be arranged on a first circuit board, and the group of second light sources can be arranged on another second circuit board. It is possible that the first light source is provided on the first circuit board allocated in the direction of the light from the first light sources to the plurality of optical senses behind the second light sources so that the second light sources provided on a second circuit board are located between the first light sources and the plurality of optical senses. In another embodiment, both groups of light sources, the first and second light sources, may be provided on the same circuit board.
Each shielding element can be formed as a hollow or tubular body enclosing at least one second light source. The hollow body then limits the light emitted by one second light source in such a way that the light emitted from a second light source hits only one of the optical lenses. Furthermore, as the shielding element separates light from one second light source from light emitted by another second light source illuminating another optical lens, different optical effects can be obtained for different optical lenses.
Each hollow body as shielding element may be located with one of the end surfaces on one of the circuit boards wherein at least one diffusing element is arranged on the other end surface of the hollow cylinder. In this embodiment, a diffusing element may close the hollow body at its upper part so that the light generated by the second light sources enclosed by the hollow body passes through a diffusing element before passing one of the optical lenses.
A diffusing element can close one end surface of the hollow body with the exception of a central part of the hollow body where the beam generating element of the first light source is provided. In this embodiment, the end surface of the hollow body facing the optical lenses is covered with a diffusing element in the part of the end surface where the light of at least one second light source is transmitted to a corresponding optical lens. The other part of the end surface is not covered by the diffusing element. Through this other part, the light emitting from the beam generating element is directly passed to the optical lens.
The illumination device may further comprise a first driver for driving the group of first light sources and a plurality of second drivers provided for driving the group of second light sources. A subgroup of the second light sources can be provided to illuminate one of the plurality of optical lenses, wherein one second driver is provided to drive the second light sources of each subgroup. In this embodiment, one second driver is provided for driving the light sources illuminating one optical lens wherein a single first driver is provided to drive all first light sources. The electric power used to drive each of the first light sources can be at least ten times higher than the electric power used to drive each of the light sources. This provides a cost effective solution for driving the different group of light sources. As a driver driving a high power first light source is much more expensive than a lower power driver driving the second light sources, a system is obtained in which only a single high power driver is used with a plurality of low power, more cost-effective second drivers. As a result, the optical lenses can act a plurality of pixels in a graphical display in a cost-efficient way.
The first light sources that are provided on the first circuit board may be provided in direction of the light from the first light source to the plurality of optical lenses behind the second light sources. This means that the second light sources provided on the second circuit board are located between the first light sources and the plurality of optical lenses. When the first circuit board with the first light sources is located behind the second circuit board, the beam generating elements pass through the second circuit board and substantially extend to the front surface of the shielding elements or beyond.
When the second light source is used to illuminate one optical lens, at least two second light sources may be used to illuminate an optical lens in order to obtain a more uniform light distribution on the optical lens.
It should be taken into account that each of the features described above or described in further detail below may be used in the described context. However, each of the features may also be used alone or in combination with any of the other features described above or below.
The illumination device can furthermore comprise an actuator which can move the optical lenses relative to the beam generating elements. This helps to generate light beams with a varying beam width and/or divergence.
In the illustrated embodiment, the head comprises a number of light sources and a number of optical lenses 109 arranged in the head housing 111. The light collecting means collect light from at the light sources and convert the collected light into a number of source light beams 113 (one being illustrated in
In the illustrated embodiment the head housing 107 is a “bucket” shaped head housing 111 wherein a display 115 (visible from the rear side of the head), main PCB 117 (Printed Circuit Board), a fan 119, a heat sink 121, an LED PCB 123, and lens assembly are stacked. The LED PCB 123 comprises a number of LEDs 124 and the lens assembly comprises a lens holder 125 with diffuser regions 126 and a lens array where the lenses constitute the light collecting means 109. Each light collecting means is adapted to collect light form one LED and convert the collected light into a number of light source beams 113. The head is rotatable connected to the yoke by two tilt bearings 127, which are supported by the yoke 105. A tilt motor 129 is adapted to rotate the head through a tilt belt 131 connected to one of the tilt bearings 127. The yoke comprises two interlocked yoke shell parts 132 which are mounted to a yoke frame 134 where on the tilt bearings, tilt motor, pan motor and pan bearing are arranged. The LED PCB 123 comprises a number of LEDs emitting light and which in cooperation with the light collecting means 109 in the lens array generate a number of light source beams. The main PCB comprises controlling circuits and driving circuits (not shown) for controlling the LEDs as known in the art of illumination devices. The main PCB comprises further a number of switches (not shown) which extend through a number of holes in the head housing 111. The switches and display act as a user interface allowing a user to communicate with the moving head lighting fixture.
The yoke is connected to a pan bearing 133 rotatable connected to the base 103. A pan motor 135 is adapted to rotate the yoke through a pan belt 137 connected to the pan bearing 133. The base comprises 5-Pin XLR male 139 and female 141 connectors for DMX signals as known in the art of entertainment lighting, input 143 and output power 145 connectors, power supply PCB's (not shown) and fan (not shown). The fan forces air into the base through vent holes 147.
This prior art illumination device of
The illuminating device illustrated in
Referring especially to
As explained in more detail in connection with
In connection with
As shown in
In
The above described embodiments provide different possibilities to illuminate the optical lenses. With the first LEDs, a narrower beam is obtained compared to the embodiment where the second LEDs are used. Furthermore, with the second LEDs, the dot-like appearance of the light sources can be avoided.
Number | Date | Country | Kind |
---|---|---|---|
14172100 | Jun 2014 | EP | regional |
Number | Name | Date | Kind |
---|---|---|---|
6402347 | Maas | Jun 2002 | B1 |
7070310 | Pond | Jul 2006 | B2 |
8061868 | Dubord | Nov 2011 | B2 |
8820963 | Olsen | Sep 2014 | B2 |
20050073848 | King et al. | Apr 2005 | A1 |
20060083016 | Okamura et al. | Apr 2006 | A1 |
20100109531 | Helms et al. | May 2010 | A1 |
20110280031 | Luger et al. | Nov 2011 | A1 |
20110285292 | Mollnow et al. | Nov 2011 | A1 |
20130170222 | Lin | Jul 2013 | A1 |
20130294045 | Morgenbrod | Nov 2013 | A1 |
20140133142 | Jørgensen | May 2014 | A1 |
20140316742 | Sun | Oct 2014 | A1 |
Number | Date | Country |
---|---|---|
201 180 949 | Jan 2009 | CN |
2008218089 | Sep 2008 | JP |
2011131197 | Oct 2011 | WO |
Entry |
---|
European Search Report for Application No. EP 14 17 2100 dated Nov. 7, 2014. |
Number | Date | Country | |
---|---|---|---|
20150362147 A1 | Dec 2015 | US |