Field of the invention

The present invention relates to an illuminating device, by which it is possible to implement energy-efficient and ecological illuminators with reasonable expenses, which illuminators produce a light beam resembling advantageously the shape of a rectangle onto a target surface, which beam is as even as possible.

The illuminating device can be applied to both indoor and outdoor illuminators. The illuminating device comprises one or more light elements as a light source, and a frame part, to which the light sources are attached.

Background of the invention

It is generally known to implement illuminators that produce a light beam, which is shaped mostly like a rectangle. They are, however, implemented with so-called conventional light sources, such as fluorescent tubes or the like.

A drawback of such illuminating devices is, inter alia, that their operating life is quite short, in which case they are not as ecological as possible. Another drawback is that the length and width dimensions of the light beam are generally not very well controllable.

Nowadays there are small, bright LED light sources, which form a conical light beam. By means of them and suitable lens optics it is possible to implement more versatile illuminators, where the produced luminous distribution pattern can be well controlled. In addition, nowadays there are computer programs, by means of which the necessary, possibly even multiform lens optics can be designed and implemented. Brief summary of the invention

It is an aim of the present invention to eliminate the above-mentioned drawbacks to a great extent and to enhance the state of the art prevailing in the field and to introduce an illuminating device for producing energy-efficient and durable illuminators for both outdoor and indoor use. The invention is based on the idea that the light elements of the illuminating device are implemented by using as light sources efficient, light-emitting semiconductors, such as LED, by placing these light-emitting semiconductors in the frame structure sequentially straight, and by arranging a light-directing element in front of the light-emitting semiconductors.

The illuminating device according to the present invention is primarily characterized in, that

- the light source is a light-emitting semiconductor structure,

- the light sources are fixed in a row formation in the frame profile,

- the illuminating device comprises a rod-like optics element, which is placed parallel in front of the row formed by the light sources so that most of the light beam of each light source travels through the lens optics and the front plate, and

- the front plate is of an at least partly light-permeable material.

The illuminating device according to the invention is suitable for implementing illuminators of very different sizes and illuminating efficiency, for both outdoors and indoors.

The present invention shows remarkable advantages over devices of prior art. With the illuminating device according to the invention it is possible to implement illuminators suitable for both general illumination and various special needs, one significant advantage of which is that with them it is possible to implement a relatively even illumination on a limited area in an energy efficient and ecological manner.

For example, street lighting and walkway lighting can be implemented with good quality, because almost all of the light produced by the light source can be utilized efficiently and unnecessary illumination of surrounding areas is decreased significantly in comparison to solutions utilizing known light sources.

The energy efficiency of illuminators implemented according to the present invention is good and as the light-emitting semiconductors are further developed, the energy efficiency is improved even more. In addition, the operating life of semiconductor light sources is multiple in comparison to conventional light sources.

Description of the drawings

In the following, the invention will be described in more detail with reference to the appended drawings, in which

Figures 1 and 2 show in a reduced cross-sectional view a light element of an illuminating device according to an embodiment of the invention seen from different angles,

Figure 3 shows an example of street lighting that is implemented with the illuminating device according to the invention,

Figure 4 shows in a reduced block chart the electric coupling arrangement of an illuminating device according to the invention,

Figure 5 shows in a simplified manner one advantageous attaching manner of the illuminating device according to an embodiment of the invention,

Figures 6 and 7 show in a reduced cross-sectional view the attachment of light sources of an illuminating device according to an embodiment of the invention by means of a separate fixing element seen from different angles,

Figures 8 and 9 show in a reduced cross-sectional view an illuminating device according to an embodiment of the invention, which device produces an as even as possible light beam resembling the shape of an "eye pattern", and Figure 10 shows in a simplified manner an illumination pattern formed by an illuminating device according to another advantageous embodiment of the invention,

Detailed description of the invention

Figures 1 and 2 show in a reduced cross-sectional view the structure of a light element of an illuminating device according to an embodiment of the invention. The dashed lines show the parts placed inside the frame profile of the light element. The light element of the illuminating device comprises one or more light sources 1 , which is a light-emitting semiconductor structure, advantageously a so-called LED (Light Emitting Diode). The light source 1 is attached to the frame profile 2, which is, for example, of heat-conductive material, such as metal, but it is obvious that other materials or combinations of materials can also be used.

In front of the light beam formed by the light sources is placed a rod- like optics element 3, which adapts the light beam of the illuminating device into a shape which advantageously resembles a rectangular shape. The cross-section of the optics element 3 is advantageously circle, half-circle, ellipsis or some other shape suitable for the purpose or a combination of such, in which case a lens reflecting rays of light is formed. By the shape of the cross-section as well as the distance between the optics element 3 and the light sources 1 it is possible to affect the shape of the light pattern created on the target, such as road surface, as well as the distribution of light intensity on the illuminated area. The object is advantageously substantially a light pattern corresponding to a rectangular shape, in which case the light is targeted as evenly as possible to the aimed part of the target surface and as little light as possible is directed outside this area.

In addition, the frame structure of the light element comprises an at least partly light-permeable front plate 4 and end pieces 5, which are attached to the frame profile.

The inner volume of the frame profile 2 can be implemented as a structure that is ventilating but dust and moisture resistant. This is possible, for example, by appropriate design of end pieces 5 and with dust and moisture filters. Thus, a good heat transfer away from the light sources 1 is created and it is possible to decrease or even prevent the formation of condensing water. A good location for the filters is typically at both end pieces 5 of the frame profile, in which case ventilation takes place efficiently.

Light sources 1 are installed substantially in a straight line in the frame profile 2 so that the light beams of the light sources are directed towards the rod-like optics element 3. The dimensions of the optics element 3 and its distance from the light sources define the properties of the desired light pattern, especially the width of the rectangular light beam. The light sources 1 can also be placed in more than one row. Thus, a separate rod-like optics element 3 is added for each row as well, or one optics element 3 designed for this purpose is used, such as a transparent piece, where the lens optics is implemented for each light source row (not shown).

Light sources 1 can also be installed to a separate fixing piece 11 , which in turn is attached to the frame profile 2. This makes it possible to change all light sources quickly at once, for example, in connection with maintenance.

Figures 8 and 9 show an advantageous embodiment of the invention, wherein the rod-like optics element 3 has a semi-circular profile, in which case the light beam of a typical LED light source is adapted to a so-called "eye pattern" 12, which is shown in figure 10. The formed light beam is advantageous from the point of view of, for example, a street light, because the light intensity increases from the middle of the "eye pattern" towards the tips of the eye pattern, in which case also the road surface located furthest from the illuminator receives the necessary amount of light. The areas outside the eye pattern can, if necessary, be illuminated by adding separate LED light sources to the illuminator, which light sources are equipped with lens optics suitable for the purpose.

Figure 10 shows an advantageous manner for illuminating the areas outside the above-mentioned eye pattern in order to illuminate with good quality a rectangular area 15, such as a narrow walkway or the like. LED light sources equipped with lens optics is installed in the frame profile 2, which light sources are directed in such a manner that the light beams 14 formed by them together illuminate the area outside the eye pattern of the targeted rectangular illumination area 15. The light beam adapted by lens optics 13 is typically formed either as narrow and circular or oval.

In an advantageous embodiment of the invention the front plate 4 has the optical properties of a light-scattering material, in which case the light emitted by the light source 1 spreads relatively evenly and the individual light sources 1 of the light element are not visible as disturbingly bright spots.

In an advantageous embodiment of the invention the front plate 4 is of so-called self-cleaning glass or a corresponding material, which is cleaned by the combined effect of UV light and rain water.

In an advantageous embodiment of the invention a structure of the device that is internally hermetically protected has been implemented by different manners known as such (not shown). This structure is suitable, for example, for illuminators in humid rooms. Thus, a sealing has been arranged in connection with the frame profile, with which the light source is made into a hermetically closed structure. Another possibility for creating a hermetically closed structure is to seal the seam between the frame profile and, for example, the front plate 4 with a sealant.

The illuminating device according to the invention can be applied in various ways. Figure 3 shows an application, where street illumination is implemented by illuminating devices according to the invention. In this application the illumination is focused on the area that is desired to be illuminated, and the surrounding areas are not unnecessarily illuminated.

The attached figure 4 shows the electric coupling principle of an illuminating device according to an advantageous embodiment of the invention. Electric energy is supplied to the illuminating device 6, for example, by adapting a higher voltage 7, such as an alternating voltage of 230 V with an adaptor 8 to a direct voltage suitable for light sources 1 , which voltage is coupled to the illuminating devices 6 according to the invention. The adaptor is, for example, an AC/DC adaptor, which adapts alternating current to direct current and at the same time decreases the voltage and current to a level suitable for the light sources 1.

Alternatively it is possible to use as light sources 1 of an illuminating device 6 such light elements, where the AC/DC-adaption and other necessary electronics are built in. Thus, the illuminating devices 8 can be coupled directly to an electrical network of 230 V, which is technique known as such to a person skilled in the art.

Alternatively the power supply of light sources 1 of the illuminating device 6 can be divided into two or more groups, which can be controlled by controller components inside or outside the illuminating device. Thus, the luminosity of the illuminating device can be controlled step by step, for example according to the illuminating level of the surroundings. The control of luminosity can also be implemented, for example, by PWM (Pulse Width Modulation) control, in which case the control is almost continuous. This is technique known as such to a person skilled in the art.

It is obvious that the present invention is not limited solely to the above- presented embodiments but it can be modified within the scope of the appended claims.