DE102015208170A1 - Irradiation device with a plurality of laser sources - Google Patents

Abstract

The present invention relates to an irradiation device (1) comprising a radiation unit (2) comprising a plurality of laser sources, a phosphor element (9) for converting the radiation, an optic (6, 7) which illuminates the radiation beams (5) in an irradiation surface (8). superimposed on the phosphor element (9), wherein in the path of the radiation from the radiation unit (2) to the irradiation surface (8) a reflection surface (11) reflective for the radiation is arranged where the radiation beams (5) are free of overlap, so that the radiation beams (5) of the laser sources on the radiation path pass the reflection surface (11), but a part of the radiation reflected back on the phosphor element (9) at least partially falls on the reflection surface (11) and is guided again to the irradiation surface (8).

Description

Technical area

The invention relates to an irradiation device with a radiation unit, which is constructed from a plurality of laser sources.

State of the art

Light sources of high luminance can be used, for example, in the field of endoscopy or in projection devices. Although gas discharge lamps are still the most prevalent at this time, recent developments have been to combine a high power density radiation source, such as a laser, with a phosphor element that converts the radiation emitted therefrom. The phosphor element is arranged at a distance from the radiation source and then converts blue or ultraviolet pump radiation into visible conversion light during operation, for example.

Presentation of the invention

The present invention is based on the technical problem of specifying a particularly advantageous irradiation device.

According to the invention, this problem is solved with an irradiation device having a radiation unit constructed from a plurality of laser sources, which laser sources are each designed to emit radiation in the form of a beam, a phosphor element for converting the radiation, an optic which superimposes the radiation beam in an irradiation surface of the phosphor element and a reflective surface reflective for the radiation, which is arranged in a path of the radiation from the radiation unit to the irradiation surface where the radiation beams are free of overlap, ie there is a space between adjacent adjacent radiation beams, wherein the reflection surface is arranged in the intermediate spaces, so that the radiation beams pass on the radiation path on the reflection surface, but a part of the radiation reflected back on the phosphor element at least partly falls onto the reflection surface and is led again to the irradiation area.

Preferred embodiments are to be found in the dependent claims and the rest of the remaining disclosure, wherein the presentation is not always distinguished in detail between device and use aspects; In any case, implicitly, the disclosure must be read with regard to all categories of claims.

In the case of the irradiation device according to the invention, therefore, a reflection surface reflective for the radiation is provided between the radiation unit and the irradiation surface in such a way that initially the ray bundles pass by on the radiation path. The "radiation path" refers to the path from the radiation unit to the irradiation surface. The inventor has found that a certain part of the radiation can be reflected back at the irradiation surface, for example due to scattering effects. This back-reflected part of the radiation takes a return path, which is opposite to the radiation path, from the irradiation surface to the radiation unit. In the case of the return reflection, the opening angle of the individual ray bundles can also be increased, for example, so that the reflected-back radiation can then fall onto the reflection surface over a comparatively large area, is reflected thereon and thus guided again to the irradiation surface.

As a result, a greater part of the radiation emitted by the radiation unit is actually also used, thus increasing the efficiency. In model calculations, the inventor has observed for an in the context of the embodiments then explained in detail arrangement with the reflection surface an increase of the proportion of actually registered in the phosphor element radiation of 84.6% without reflection surface to 91.1% with reflection surface (each of the the radiation unit emitted radiation). This is already close to an ideal value of 93.4%, which results in a calculation without phosphor element (a loss of 6.6% occurs in the rest of the optical design).

In this case, the reflection surface reflective for the radiation is arranged there in the radiation path where the radiation beams do not overlap and there are correspondingly intermediate spaces between them. In these intermediate spaces and thus between the radiation beams, the reflection surface is arranged, so that the radiation beams pass on the radiation path on the reflection surface. Two nearest adjacent radiation beams are "overlapping-free" if their lateral surfaces do not intersect or touch, ie are spaced apart from one another. Preferably, a minimum taken from lateral surface to lateral surface distance of at least 1/10, 1/5, 3/10, 2/5, 1/2, 3/5, 7/10, 4/5 and 9/10 of the middle Diameter of the two considered bundles of rays in the plane of the reflection surface. The diameter of a beam results as the average value of its smallest and largest extent perpendicular to the main propagation direction of the beam. The "mean diameter" is the average of the two beam diameter.

The lateral surface of a beam should in a direction of the main propagation of the Seen beam bundle vertical sectional plane considered where the radiation power has dropped to half of the maximum; this definition is preferred, in general the edge could, for example, also be placed where the radiation power has fallen to 1 / e. The "main direction" of a ray bundle results in the respectively considered section as the mean value of all the direction vectors of the ray bundle, wherein in this averaging each direction vector is weighted with its associated beam strength.

In general, a bundle of rays in the region of the reflection surface does not have to be present without overlap with all the bundles of rays nearest to it, but can, for example, in the case of a matrix-like arrangement (see below in detail), be free of overlap. Also only between the rows, but not within the rows or between the columns, but not within the columns. Preferably, however, all the radiation beams are free of overlaps.

For example, by definition, those beams may be considered to be "nearest" to a beam that is intersected by a circle drawn about that center axis in a plane perpendicular to the center axis of the beam. The "center axis" is parallel to the main direction of propagation of the beam in the considered section and extends centrally in the beam, so in a plane perpendicular to the Hauausbreitungsbene cutting plane viewed in the centroid (the cross-sectional area of the beam, taken to the outer surface). The radius of the circle should correspond to 1.5 times the smallest distance, which results in a comparison of the distances taken in each case from the center axis of the observed beam to the central axes of the surrounding beam.

The reflectance of the reflection surface should (at least over the spectral range of the radiation, ie the laser radiation) at least 85%, in this order increasingly preferably at least 86%, 87%, 88%, 89%, 90%, 91%, 92 %, 93%, 94% and 95%, respectively. Preferably, a metallic material forms the reflective surface, such as aluminum or silver.

In a preferred embodiment, the reflection surface is flat, that is flat. More preferably, the planar reflection surface lies in a plane on which each of the radiation beams is perpendicular with its respective main propagation direction.

In a preferred embodiment, the reflection surface is a contiguous surface which is interrupted in each case in a hole-shaped manner for at least a part of the radiation bundles, namely at least for the centrally located radiation bundles. A "hole-shaped interruption" is peripherally bordered by the reflection surface (with respect to their surface directions), that is, bounded in the plane of the reflection surface circumferentially thereof. The outboard beams generally need not be completely enclosed by the reflective surface; Preferably, however, the reflection surface is interrupted in each case in a hole-shaped manner for each of the ray bundles. The shape and orientation of a hole-shaped interruption preferably corresponds to the shape and orientation of the respective beam (in a plane containing the reflection surface of the reflection layer), which allows a reflection layer of the largest possible area.

The laser sources are preferably laser diodes. In the radiation unit, the laser sources are preferably housed together, that is, for example, mounted on a common carrier and preferably held together in a volume closed off to the outside with, for example, a (transmissive) cover plate.

In a preferred embodiment, the laser sources are arranged in the form of a matrix and also the hole-shaped interruptions in the reflection surface are arranged corresponding to a matrix. "Matrix-shaped" means in rows and columns, each with at least two laser sources or two hole-shaped interruptions; Preferably, the number of hole-shaped interruptions per row and column is equal to the number of laser sources (see above).

In general, the matrix-shaped arrangement does not necessarily have to be regular, preferably the rows are straight and / or the columns are straight, particularly preferably both. Preferably, the line spacing (the distances of immediately consecutive lines) with each other and / or the column spacing (the distances of immediately consecutive columns) are constant with each other, particularly preferably both. In the case of the laser sources, in this case, ie for determining the row / column distances, the center of mass of the respective light emission surface is used as the basis for each laser source. In the case of hole-shaped interruptions, the center of each is used; the center of a hole-shaped interruption is equal to the centroid of an imaginary, the hole-shaped interruption filling up to their border surface.

In a preferred embodiment, the reflection surface is formed on a base body which is perforated congruently with the hole-shaped interruptions, preferably as a stamped part. In this case, the main body itself, so a Surface thereof, the reflection surface form, such as in the case of a perforated aluminum sheet. On the other hand, it is also possible to apply a further thinner layer, as a rule thinner compared to the main body, to the base body as a reflection layer, for example a silver layer whose surface then forms the reflection surface. In any case, the basic body which is congruent with the hole-shaped interruptions is preferably not transmissive to the radiation.

In another preferred embodiment, a body transmissive to the radiation is provided, on which a reflection surface forming reflection layer is arranged. The base body is not interrupted in this case in the region of the hole-shaped interruptions of the reflection surface, but formed continuously, is thus irradiated by the beams in operation. Preferably, the base body is provided in this case made of glass; On the main body, the reflective layer may be deposited, for example. Vapor deposited or sputtered.

In a preferred embodiment, the optics, which superimposed on the radiation beam in the irradiation surface, for superimposing the beam on a converging lens. Preferably, this convergent lens, which penetrate all the beam bundles, a micro-lens array with a plurality of juxtaposed micro-collection lenses (hereinafter also only "microlenses") upstream (with respect to the radiation path). The microlenses of the microlens array are arranged "side by side" with respect to the radiation path, ie connected in parallel; on the radiation path, therefore, the radiation which has fallen through a microlens does not penetrate another of the microlenses arranged next to one another.

The radiation falling on the microlens array is subdivided by it into sub-beams, into a sub-beam per microlens. With each beam, several microlenses are irradiated at the same time, so there are then each several sub-beams before. The converging lens then superimposes the partial beam bundles in the irradiation surface, preferably congruently. Thus, a uniform irradiance distribution can be achieved. This can be a significant advantage of the combination of microlens array and condenser lens.

Incidentally, the "irradiation surface" of the phosphor element is actually the irradiated region thereof, that is, it may be, for example, a subregion of a surface area of the phosphor element which is larger in terms of surface area.

"Microlens array" can be read on both a single and a double microlens array, in the latter case, the microlenses are each pairwise connected in series in series. The two-fold microlens arrangement is so far constructed of two successively arranged simple microlens arrays, the microlenses of the second arrangement should correspond to those of the first in terms of size, shape, relative to each other (within the respective microlens array) and focal length. The microlens arrays are then provided in such a way that each microlens of the first array interacts in pairs with one microlens of the second array, ie each sub-beam just described penetrates exactly one microlens of the first and exactly one microlens of the second array (within the acceptance angle range). ,

For each pair of microlenses, the rear microlens is preferably located in the back focal plane of the front microlens, and the front microlens in the front focal plane of the rear microlens. The terms "front" / "rear" and "upstream" / "downstream" generally refer in the context of this disclosure to the radiation path (from the radiation unit to the irradiation surface).

In a preferred embodiment, the reflection surface is integrated into the optics. Preferably, a reflection layer forming the reflection surface is arranged between the microlens arrangement and the converging lens, for example on an exit surface of the microlens arrangement. Generally, "integrated" in the optics means that the reflective surface is located on the first entrance surface of the optic or its last exit surface, or between the two; Thus, for example, it is also possible for an above-described perforated metal sheet, for example a stamped part, to be placed between the microlens arrangement and the converging lens. Preferably, an integration of the reflection surface is such that a reflection layer forming the reflection surface is applied to a lens of the optics.

In a preferred embodiment, the converging lens is a lens system constructed from a plurality of individual lenses, and at least one of these individual lenses is plano-convex. The reflection surface is then preferably formed on a reflection layer arranged on the flat side of this plano-convex single lens. In this case, the abovementioned body transmissive to the radiation is then the plano-convex lens. An advantage of this integration may, for example, be that fewer items must be adjusted relative to each other.

In the following, reference is made to a "total principal ray" of the ray bundles, which results as the mean value of the rays of the individual ray bundles weighted in each case with their ray intensity. Each of the beams may be described with a plurality of beams, and in averaging, an average is formed over the entirety of these beams of the beams. The total main beam is considered in the plane of the reflection surface. In this plane, the base point of the overall main beam may, for example, be the centroid of the cross-sectional areas of the radiation beams (considered in the same plane), the cross-sectional areas being weighted in each case with the irradiance. The direction of the overall main beam may be obtained as the average of all the main beam propagation directions weighted by the respective beam strength (the beam) and is preferably perpendicular to the plane of the reflection surface. For example, the overall main beam can also coincide with an axis of symmetry about which the cross-sectional areas of the radiation beams (in the plane of the reflection surface) are rotationally symmetrical to each other.

In a preferred embodiment, an optical axis of the converging lens and the total main beam are offset from each other. They thus extend with a certain distance from one another and preferably parallel to one another. For example, in the case of a matrix-like arrangement of the laser sources described above, the proportion to which the backscattered light passes by a hole-shaped interruption on the reflection surface, for example. T. let reduce significantly. The "optical axis" of the converging lens is an axis of symmetry to which one or the curved refractive surface (s) of the lens is at least rotationally symmetric, preferably rotationally symmetrical.

The inventor has found that in the case of the return reflection at the irradiation surface, a directed portion can at least contain and even be dominant. In other words, not all the light reflected back is scattered diffusely, but a sometimes considerable part is reflected according to the law of reflection (angle of incidence = angle of reflection). If the total principal ray and the optical axis of the condenser lens coincided, in the case of a regular arrangement of the radiation sources (which is preferred) then the part of a radiation beam reflected at the irradiation surface would take a path exactly opposite the radiation path of another radiation beam. As a result, the radiation reflected at the irradiation surface would, for example, pass the reflecting surface through a hole-shaped interruption associated with another beam. The offset, on the other hand, does not accurately mirror from a hole-shaped break to a hole-shaped break.

In the foregoing, reference has already been made to the distance d (taken in the plane of the reflection surface) from the beam center axis to the beam center axis, which a radiation beam has in each case to one of its nearest neighboring radiation beams. In a preferred embodiment, the optical axis of the converging lens and the total principal ray are offset by at least (1/8) * n * d and by at most (3/8) * n * d, where n is a natural number ≥ 1. The upper and lower limits are based on the same natural number. Preferably n is not greater than 10, 5 or 2, preferably n = 1. Preferably, an offset between the total principal ray and the optical axis of the converging lens is (1/4) · n · d. As a distance d is preferably based on the smallest distance, which results in consideration of all distances between each next adjacent beam.

In a preferred embodiment, the optical axis of the condenser lens and the overall main beam are offset from one another in a direction parallel to a row or column of the matrix-shaped arrangement of the hole-shaped interruptions (see front). Preferably, the rows and columns are mutually equidistant (the row and column distances are generally taken from center axis to center axis); in the case of the line-parallel offset corresponds to the above-referred to distance d then the distance of the columns, whereas in the case of column-parallel offset of the line spacing specifies the distance d.

In general, the radiation beams emitted by the laser sources preferably have an aspherical, for example elliptical beam bundle cross section (in a sectional plane perpendicular to the respective center axis). Preferably, the hole-shaped interruptions are also aspherical; such an aspherical hole-shaped interruption has an axis of the largest and an axis of the smallest extent, which axes are perpendicular to each other, for instance in the case of the elliptical shape.

In a preferred embodiment relating to the aspheric hole-shaped interruptions, the optical axis of the condenser lens and the overall main beam are offset from each other in a direction parallel to the axis of the smallest extent. If the line spacings are, for example, the same size as the column spacings, then advantageously the larger interspace can be used for the reflection.

The invention also relates to the use of a presently disclosed Irradiation device for automotive exterior lighting. Advantageous fields of application can also be in the field of effect lighting; on the other hand, the irradiation device can also serve surgical field illumination; The irradiation device can also be used as a light source of a projection device, endoscope or stage headlamps, such as scene lighting in the film, television or theater area.

Brief description of the drawings

In the following, the invention will be explained in more detail with reference to an embodiment, wherein the individual features in the context of the independent claims in another combination may be essential to the invention and continue to distinguish not in detail between the claim categories. In detail shows

1 an irradiation device according to the invention in a schematic section;

2 the reflection surface of the irradiation device according to 1 in a supervision;

3 an offset between the condenser lens of the irradiation device according to 1 and a total main beam;

4 a section of the microlens array of the irradiation device according to 1 in an oblique view;

5 a further irradiation device according to the invention in a side view.

Preferred embodiment of the invention

1 shows an irradiation device according to the invention 1 with a radiation unit 2 , namely 20 housed together laser diodes (not shown in detail in the illustration). The laser diodes are arranged in four lines of five laser diodes, with the line spacing at 2.75 mm and the column spacing is 2 mm. The laser diodes are oriented so that each of the slow axis line and the fast axis is parallel to the column. The outer dimensions of the housing (including laterally protruding fastening webs 3 ) are 17.5 × 12.75 mm ² .

The radiation unit 2 Immediately downstream are collimating lenses 4 arranged, which are in the present case designed as cylindrical lenses. Each of the laser diodes emits a beam 5 , where the ray bundles 5 With the cylindrical lenses collimated only with respect to the fast axis, in the direction of the slow axis, the divergence is much lower anyway. In the present case, the collimating lenses are used 4 at the same time as a closure cover of the housing with the laser diodes.

The collimating lenses 4 Downstream the beams meet 5 on a microlens array 6 , in the 4 in an enlarged view and oblique view is shown. It is a double microlens arrangement with entry-side microlenses 6a and exit side microlenses 6b , Each of the beams 5 falls on several entry-side microlenses 6a at the same time and is subdivided into a corresponding number of sub-beams (one microlens each). Each of the sub-beams then hits exactly one associated exit-side microlens 6b , Each entry-side microlens 6a forms each with an exit-side microlens 6b a functional couple.

The microlens arrangement 6 downstream is a condenser lens 7 provided, in this case, an aspherical single lens, which of the microlens array 6 generated partial beam in an irradiation surface 8th superimposed. In this case, with each sub-beam, the entire irradiation surface 8th irradiated, resulting in a result to a homogeneous irradiance distribution. The irradiation area 8th lies on a side surface of a phosphor element 9 , The phosphor element 9 is excited with the radiation generated by the laser diodes and emits to this excitation radiation of longer wavelength, namely visible light. Due to the combination of microlens arrangement 6 and condenser lens 7 can achieve a uniform irradiance distribution and thus a local overheating of the phosphor element 9 be prevented.

Not the entire on the irradiation area 8th However, falling radiation is actually converted, but some of it is reflected back, for example due to scattering processes.

In the irradiation device according to the invention 1 is therefore a reflection layer 10 with one of the irradiation surface 8th facing reflection surface 11 intended. In the present case, this is an aluminum sheet whose irradiation surface 8th facing surface is silvered. In the aluminum sheet are hole-shaped interruptions 12 stamped, through which the beams 5 pass through and thus on the reflection surface 11 can pass by.

2 shows the reflection surface 11 with the hole-shaped interruptions 12 in a plan view, in one direction, the radiation path (from the radiation unit 2 to the irradiation area 8th ) looking at it opposite. The hole-shaped interruptions 12 are each elliptical, in adaptation to the cross-sectional shape of the beam 5 , The gaps 20 between the beams 5 So, as far as possible, they are filled up with mirror surface, which helps to increase efficiency.

3 shows a view from the same direction as 2 , where additionally the reflection surface 11 downstream collecting lens 7 is shown. Out of the drawing plane, the structure is thus: radiation unit 2 (with the visible fastening bars 3 ), Collimating lenses 4 and microlens array 6 (both not visible), reflection layer with reflection surface 11 and condenser lens 7 , The condenser lens 7 has an optical axis 30 , which is perpendicular to the drawing plane.

Further, in the figure, a total main beam 31 characterized, which is an average value of all rays of the beam 5 results (the individual beams are each weighted with their beam strength). The main beam 31 is perpendicular to the reflection surface 11 (and thus the drawing plane) and lies on an (not shown) symmetry axis, around which the hole-shaped interruptions 12 are rotationally symmetric.

Out 3 it can be seen that the main beam 31 and the optical axis 30 the condenser lens 7 in one to the reflection surface 11 are offset parallel to each other, in a line-parallel direction. The offset is one quarter of the column spacing, ie 0.5 mm.

Assuming for purposes of illustration a specular reflection on the irradiation surface 8th , would due to the rotationally symmetrical arrangement of the hole-shaped interruptions 12 one by one interruption 12 passing beam (after the assumed specular reflection at the irradiation surface 8th ) pass through a 180 ° rotationally symmetrical hole-shaped interruption and thus not on the reflection surface 11 be reflected. As a result of the offset, the reflected radiation does not fall through the respectively assigned interruption, which is rotationally symmetrical about 180 ° 12 but on the reflection surface 11 , Since the offset is one quarter of the column spacing, that falls on the irradiation surface 8th (imputed) specularly reflected radiation exactly between two interruptions 12 ,

Now the rays become 5 in realiter at the irradiation area 8th Although not speculatively reflected, however, there may be a considerable speculative share. This falls due to the offset on the reflection surface 11 and so again in the direction of the phosphor element 9 guided.

4 shows the microlens array 6 the irradiation device 1 according to 1 in detail in an oblique view. It is a monolithic, ie in a molding process (in this case by injection molding) manufactured part, its entrance and exit side each with a plurality of microlenses 6a , b are shaped.

5 finally shows a second irradiation device according to the invention 1 , the radiation unit 2 , the collimation lenses 4 , the microlens arrangement 6 and the phosphor element 9 with the irradiation surface 8th are identical to the irradiation device 1 according to 1 intended; Reference is made to the above description. In contrast to the irradiation device 1 according to 1 is the condenser lens 7 in the present case, however, not designed as a single lens, but as a lens system of two individual lenses 7a , b. These are two plano-convex lenses 7a , b. Functionally, however, there is no difference, the two individual lenses 7a , b act together as a converging lens and superimpose those of the microlens array 6 generated partial beams in the irradiation surface 8th (see the above description).

In the irradiation device 1 according to 1 is now the reflection layer 10 directly onto the first single lens with respect to the radiation path 7a of the collective lens system 7 applied, on the microlens array 6 facing entrance surface. It is therefore applied to this plane entrance surface a silver coating. This silver coating is structured, so with (in the side view unrecognizable) hole-shaped interruptions 12 for the beams 5 Mistake.

Claims (15)

Irradiation device ( 1 ) with a radiation unit constructed from a plurality of laser sources ( 2 ), which laser sources in each case for the emission of radiation in the form of a beam ( 5 ), a phosphor element ( 9 ) for the conversion of the radiation, an optic ( 6 . 7 ), which the bundles of rays ( 5 ) in an irradiation area ( 8th ) of the phosphor element ( 9 superposed, and a reflective surface reflective to the radiation ( 11 ), which are in a path of radiation from the radiation unit ( 2 ) to the irradiation surface ( 8th ) is located where the radiation beams ( 5 ) are overlap-free, ie between nearest neighboring beams ( 5 ) each finds a gap, wherein the reflection surface ( 11 ) is arranged in the intermediate spaces so that the radiation beams ( 5 ) on the radiation path at the reflection surface ( 11 ), one on the phosphor element ( 9 ) back-reflected part of the radiation, however, at least in part on the reflection surface ( 11 ) and so again to the irradiation area ( 8th ) to be led. Irradiation device ( 1 ) according to claim 1, wherein the reflection surface ( 11 ) is plan. Irradiation device ( 1 ) according to claim 2, wherein the reflection surface ( 11 ) lies in a plane on which the radiation beams ( 5 ) are each perpendicular to their respective Hauptausbreitungsrichtung. Irradiation device ( 1 ) according to one of the preceding claims, in which the reflection surface ( 11 ) is a contiguous surface which is responsible for at least a part of the radiation beams ( 5 ) each interrupted hole-shaped ( 12 ), preferably for all radiation beams. Irradiation device ( 1 ) according to claim 4, wherein the laser sources are arranged in matrix form and also the hole-shaped interruptions ( 12 ) in the reflection surface ( 11 ) are arranged corresponding matrix-shaped. Irradiation device ( 1 ) according to claim 4 or 5, wherein the reflection surface ( 11 ) on a base body ( 10 ) formed with the hole-shaped interruptions ( 12 ) of the reflection surface ( 11 ) is perforated congruent, preferably as a stamped part. Irradiation device ( 1 ) according to claim 4 or 5, wherein the reflection surface ( 11 ) on a reflection layer on a body transmissive to the radiation ( 7a ), which basic body ( 7a ) in the area of the hole-shaped interruptions ( 12 ) of the reflection surface ( 11 ) is formed continuously. Irradiation device ( 1 ) according to one of the preceding claims, in which the optics ( 6 . 7 ) a condenser lens ( 7 ) comprising the radiation beams ( 5 ) in the irradiation area ( 8th superposed, and preferably one of the convergent lens ( 7 ) upstream microlens array ( 6 ) with a plurality of juxtaposed micro-collection lenses. Irradiation device ( 1 ) according to claim 8, wherein the reflection surface ( 11 ) into the optics ( 6 . 7 ) is integrated. Irradiation device ( 1 ) according to claim 9 in conjunction with claim 7, wherein the convergent lens ( 7 ) one of a plurality of individual lenses ( 7a , b) constructed lens system, wherein at least one of these individual lenses ( 7a , b) is plano-convex and the reflection surface ( 11 ) at one on the plane side of this plano-convex single lens ( 7a , b) arranged reflection layer ( 10 ) is trained. Irradiation device ( 1 ) according to one of claims 8 to 10, in which the radiation beams ( 5 ) around an overall main beam ( 31 ) and the convergent lens ( 7 ) an optical axis ( 30 ), the optical axis ( 30 ) of the condenser lens ( 7 ) and the overall main beam ( 31 ) are offset from each other. Irradiation device ( 1 ) according to claim 11, in which a radiation beam ( 5 ) to a next adjacent beam ( 5 ) has a distance d, wherein the optical axis ( 30 ) of the condenser lens ( 7 ) and the overall main beam ( 31 ) are offset by at least (1/8) · n · d and by at most (3/8) · n · d with n = {1, 2, 3, ...}. Irradiation device ( 1 ) according to claim 5 in conjunction with claim 11 or 12, in which the optical axis ( 30 ) of the condenser lens ( 7 ) and the overall main beam ( 31 ) are offset from one another in a direction parallel to a row or a column of the matrix-like arrangement of the holes ( 12 ) lies. Irradiation device ( 1 ) according to claim 5 in conjunction with any one of claims 11 to 13, wherein the hole-shaped interruptions ( 12 ) are aspherical and each have an axis of the largest and an axis of the smallest extent, wherein the optical axis ( 30 ) of the condenser lens ( 7 ) and the overall main beam ( 31 ) are offset from each other in a direction parallel to the axis of the smallest extent. Use of an irradiation device ( 1 ) according to one of the preceding claims for motor vehicle exterior lighting, effect or surgical field illumination or as a light source of a projection device, endoscope or stage headlamp.

Images