DE102014018821B4 - diode laser attachment - Google Patents

Abstract

Laser module (1), comprising a carrier element (2), a diode laser element (3), a bracket (4) and a clamping element (5), wherein the diode laser element (3) comprises at least one diode laser bar (8) with at least one first contact surface (9). and a second contact surface (10), a first heat conduction body (11) thermally and electrically connected to the first contact surface and having a heat dissipation surface (12), and a lid (13), the stirrup having a front portion (21), a base portion (22), and a support portion (23), the front portion comprising a power transmission portion (16) and a bending beam portion (19), and a hinge (25 and 27) is provided between the support portion and the base portion (22); wherein the bending beam portion (19) relative to the base portion (22) has a first taper (30) and / or the bending beam portion (19) opposite the power transmission portion has a second Verjüngun g (31), and the tensioning element (5) causes elastic deflection of the bending beam section (19) by a tensioning force (7) and the link in the power transmission section exerts a force (29) on the cover of the diode laser element and the force (29) applies to the diode laser element the support element (2) presses.

Description

Technical area

The invention relates to the attachment of a diode laser element with two electrical contacts, which comprises a laser bar and a heat conducting body on a support element, which may be formed, for example, as a heat sink. The diode laser element is thermally connected to the heat sink for heat dissipation.

State of the art

Out DE 10 2008 026 229 A1 a diode laser element with two heat conduction bodies is known, which are connected via a joint layer. Out DE 10 2008 026 801 A1 a method for assembling a diode laser with two heat conducting bodies is known, in which the two heat conducting bodies are connected by means of a joining agent layer. Such diode laser elements require attachment to a heat sink, which can be accomplished by screws according to the prior art. For example, it is off DE 10 2008 027 468 A1 a laser module is known in which a diode laser element, which comprises two Wärmeleitkörper, between which is a laser bar. This laser element is fastened by means of a screw on a heat sink. This attachment has the disadvantage that a through hole is required by the laser element. In addition, the pressure force by the screw is indefinite and uneven. Out DE 10 2009 040 835 A1 a diode laser element is known in which the laser bar is not soldered, but is clamped between two Wärmeleitkörpern. A screw fastening of such a laser element has the disadvantage that it can lead to a beak-like opening of the gap between the Wärmeleitkörpern in which the laser bar is located, so that the cooling of the laser bar in the facet can be deficient.

Out WO 97/03 487 A1 a laser module is known in which a plurality of laser bars are stacked directly one above the other. The stack is clamped by means of a Schaubzwinge or by means of a tensioning device of a rigid bracket and a U-shaped leaf spring. The individual bars are not provided with individual Wärmeleitkörpern. The entire stack can only be cooled on one side over the base. This laser module can only be operated in pulse mode. Due to the low heat dissipation no continuous wave operation (cw) is possible. The compressive force on the billet stack can be undefined or uneven. This can lead to mechanical stresses and voids within the stack, causing the laser module can fail.

Out GB 1096575 A For example, a semiconductor chip clamping device is known that has two rigid legs.

Out US 2005/0069266 A1 a laser module is known in which laser elements are elastically clamped with a transversely deformable coil electrode. A disadvantage is the small spring travel, which can have a decrease in the clamping force result.

Out US 2013/0003764 A1 a laser module is known in which a laser element is clamped with a rigid strap. Disadvantageously, the clamping force is difficult to control in this arrangement.

Out US 5592021 A For example, a terminal for an electronic component is known, which is encapsulated in an epoxy resin block (TO-220, TO2018 or TO-247). The component is cooled here only on one side. The clamp is made of a material of uniform thickness, with no hinge provided. This can lead to shear forces on the component. Such shear forces are harmless for encapsulated electronic components in the above-mentioned housing. However, diode laser elements do not tolerate mechanical shear stresses during operation. In addition, no tapered bending beam section is provided. As a result, the pressure of the component can be uneven. Therefore, clamps of this known type can not be used for diode laser elements.

Another clamp is off US 4259685 A known. This clamp is made of a thin sheet metal and therefore has only a small pressure force, which would not be sufficient for cooling a diode laser. The compressive force is small and there is also no joint provided. Therefore, this terminal can not be used for diode lasers.

Two more terminals are off US 5825088 A and US 5825089 A known. These clamps have a low pressure force.

Out US 6282761 B1 a clamping device for a heat sink is known. Here a rigid pressure arm is used. This device has the disadvantage that it must be tightened now and then. Therefore, no maintenance-free operation is possible. Another disadvantage is that two screws are required as clamping elements. In addition, the joint is located at an elevated position relative to the point of pressure transfer, so that the force is not fixed to the component to be clamped in the vertical direction, ie parallel to the screw. As a result, harmful lateral forces can act on the component.

Object of the invention

The object of the invention is to provide a laser module, i. a device for emission of laser radiation to specify, in which a diode laser element, which comprises a heat conducting body and a lid, is mounted on a carrier element. It may be the attachment of one or more diode laser elements on a support element. In particular, such diode laser elements are to be fastened, in which the cover is likewise provided for heat conduction.

The attachment of the diode laser element on the support element should be made with a reproducible pressure force, the distribution of the compressive force should be reproducible and it shear forces, i. Force components parallel to the base, to be avoided. The attachment should be long-term stable and easy to replace in case of service to replace the laser element.

Solution of the task

The object is achieved by a laser module, which comprises a carrier element, a diode laser element, a bracket and a clamping element. The diode laser element has at least one diode laser bar with at least one first contact surface and a second contact surface, and a first heat conducting body, which is thermally and electrically connected to the first contact surface. The first heat-conducting body has a heat-dissipating surface and comprises a lid. The bracket includes a front portion, a base portion, and a support portion. The front portion includes a power transmission portion and a bending beam portion. Between the support portion and the base portion, a hinge is provided. The clamping element causes by a clamping force an elastic deflection of the bending beam section. Thereby, the bracket in the power transmission section exert a force on the cover of the diode laser element, wherein the force presses the diode laser element on the support member.

The method according to the invention for fastening the above-mentioned diode laser element to the abovementioned carrier element by means of the abovementioned stirrup comprises the following steps: a) providing the diode laser element, the carrier element and the stirrup; b ) Arranging the diode laser element on the carrier element; c ) Providing the tensioning element; d ) Clamping the clamping element. When clamping the clamping element occurs a deformation of the joint. A leading edge of the yoke first presses on the lid, and during clamping, an elastic deflection of the bending bar section continues to occur. Along with the deflection of the beam portion, the angle α between the front portion of the yoke and the normal of the pressure surface of the lid changes.

Advantages of the invention

With the invention, a diode laser element can advantageously be fastened on a carrier element. It is also possible to save a plurality of diode laser elements to save space on a support element. The attachment is long-term stable. Unintentional loosening of the connection, which can occur in conventional fasteners as a result of relaxation of the clamping force of a screw, is avoided by the solution according to the invention. In addition, the attachment is made with a reproducible and uniform pressure force. Furthermore, harmful lateral forces can be avoided. The specified fastening method is easy and fast to carry out and leads to reproducible results. Thus, a particularly high quality in the attachment of diode laser elements can be achieved.

The use of the clamp for fastening a plurality of laser elements on a carrier element allows a space-saving arrangement of the laser elements.

description

A device for emitting laser radiation, referred to as laser module for short, is described. For better understanding, a Cartesian xyz coordinate system can be used to describe the directions.

The laser module comprises a diode laser element. A diode laser element is a device for emitting laser radiation which has at least one diode laser bar as the beam source. The diode laser bar can be formed in a known manner as an edge-emitting component and comprise one or preferably a plurality of emitters, which can be arranged offset to one another in a direction which can be selected as the y-direction of the coordinate system. The laser bar may preferably have a width between 3 mm and 12 mm in this direction. He prefers between 3 and 120 Emitter have, particularly preferred 5, 7 or 19 or 49 Emitter. The center distance of adjacent emitters may preferably be between 0.15 mm and 1 mm. There may be areas between the emitters that emit no laser radiation. The thickness of the laser bar may preferably be between 0.05 mm and 0.2 mm in a z-direction. The resonator length of the emitter of the laser bar may preferably be between 0.5 mm and 6 mm. The x-direction of the coordinate system may be in the direction of the resonators the emitter of the laser bar, that is, in the direction of the normal of the mirror, which limit the resonator. The direction of the central rays of the emitted laser radiation may be the -x direction. The directions x, y and z may be orthogonal to each other and span the above-mentioned Cartesian xyz coordinate system. The laser bar can have a known epitaxially produced layer sequence as a pn junction with a quantum well. The individual emitters can be designed as broad-band emitters. It is also possible for there to be a plurality of layer sequences each having at least one quantum well, ie a plurality of pn junctions lying electrically in series. Such bars are also called nanostack. Then several emitters are stacked in z-direction.

The laser bar is pumped by an electric current. For current input, a first contact surface and a second contact surface are provided on the laser bar. The first contact surface may be formed as an anode (p-contact), while the second contact surface may be formed as a cathode (n-contact).

The laser bar may be configured to autonomously emit laser radiation when pumped. The wavelengths of the radiation emitted by the individual emitters can be the same. However, it is also possible to use a laser bar which is only provided in cooperation with an external resonator for emitting laser radiation. The wavelengths of the individual emitters can, but need not, be successively offset from one another. Such an offset can be achieved, for example, with a grating in the external or in the internal resonator, by means of which a specific wavelength is fed back for each emitter. The laser bar can also be designed as an optical amplifier that amplifies incident seed radiation. In this case, a laser bar is understood as meaning an optical amplification element which generates laser radiation and which is electrically pumped via at least one pn junction.

The laser bar can develop waste heat during operation, which must be dissipated. For this purpose, a heat-conducting body is provided. The heat-conducting body can dissipate the waste heat of the laser bar from the first contact surface. The waste heat can for the most part arise in the emitter strips of the laser bar, while no heat is generated in the areas between the emitters. Therefore, the heat-conducting body can also be provided to spread the heat flow in order to release the heat via the heat-emitting surface. In order to absorb the waste heat from the laser bar, the laser bar is thermally connected to the first contact surface. In addition, the first contact surface of the laser bar is electrically connected to the heat conducting body. This has the advantage that the diode laser element can be electrically contacted by means of the heat conducting body. The heat-conducting body may advantageously be electrically conductive, it may for example consist of a metal, a metal composite material such as copper-diamond or silver-diamond. The heat-conducting body can also consist of an electrically insulating material, for example ceramic, for example AIN or BeO. The heat-conducting body can also consist of pyrolytic graphite or comprise such a material. The heat-conducting body can be coated metallically. The connection of the laser bar to the heat-conducting body can be designed as a solder joint with a metallic solder, for example a gold-tin solder or a soft solder containing tin and / or indium. However, the compound can also be produced with an intermediate layer, for example of indium, by pressing, without the indium layer being brought to melt. In this case, it may be a clamp connection. Instead of an indium layer, for example, a carbon foil may also be used in the case of a clamping connection. The heat-conducting body may have a heat-releasing surface. The heat transfer surface may advantageously be designed as a flat surface. The heat release surface may lie in an xy plane and have a normal in the z direction. The heat-dissipating surface may preferably be connected over its full area to a carrier element. The support member may be formed as a heat sink. Channels for a coolant may be provided in the carrier element. The coolant can be supplied or removed via coolant connections.

The diode laser element may also include a lid. The lid may preferably also be provided for heat dissipation contributing. The lid may for this purpose be thermally connected to the second contact surface of the laser bar. It may be particularly advantageous to connect the lid also electrically with the second contact surface. This has the advantage that the diode laser element can be electrically contacted by means of the cover. The cover may advantageously be electrically conductive, it may for example consist of a metal, a metal composite material such as copper-diamond or silver-diamond. The cover may also consist of an electrically insulating material, such as ceramic, for example AIN or BeO. The lid may also consist of pyrolytic graphite or comprise such a material. The lid can be coated with metal. The connection of the laser bar to the cover can be designed as a solder connection with a metallic solder, for example a gold-tin solder or a solder, which contains tin and / or indium. However, the compound can also be produced with an intermediate layer, for example of indium, by pressing, without the indium layer being brought to melt. In this case, it may be a clamp connection. Instead of an indium layer, for example, a carbon foil may also be used in the case of a clamping connection.

The cover may be mechanically connected to the heat-conducting body via a joining zone. The joining zone may arise because a gap between the heat conducting body and the lid is completely or at least partially filled with an electrically insulating joining agent. The joining zone can be designed such that a heat transfer between the lid and the heat conducting body is possible. The diode laser bar may be connected to the second contact surface areally with the lid. The cover can be connected to the first heat-conducting body over an electrically insulating joining agent layer. The joining agent layer may be a thermal adhesive.

Furthermore, a bracket is provided. A bracket is a fastener with which a laser element can be mounted on the support element. Instead of "bracket" you could also use the term "clamp". The bracket comprises a front portion and a base portion which can be connected to the front portion in the x direction. The front portion may extend from the laser element in the x direction to the tension member, and the base portion may then connect in the x direction beyond the tension member. As a reference coordinate, the x-coordinate of a center line of the clamping element can be assumed. The base section can thus represent an extension of the front section in the x direction. The bracket may be mirror-symmetrical with respect to an xz plane.

The bracket further comprises a support portion. The support portion may be provided for supporting the bracket in the -z direction. The support portion can transmit a bearing force from the base portion to the support member, wherein the support force can act in the -z direction.

Between the base portion and the support portion, a hinge is provided. The joint may be formed as a hinge, which has at least one axis of rotation in the y-direction. By the hinge, a change of the angle between the base portion and the support portion can be made possible. It may, but need not, be provided, for example, further axes of rotation in the x-direction and / or in the z-direction.

The front portion includes a power transmission portion. The power transmission section serves to transmit a force to the cover. The force can be transferred flat. For this purpose, a printing surface can be provided on the lid. This can be the top side of the lid (xz-plane) in the side view. This surface can be parallel to the heat transfer surface. The force can be transferred flat from the power transmission section to the cover. But it is also possible to transmit the force linear or punctiform from the power transmission section on the lid. In the case of a linear force transmission, the force can be transmitted along a front edge of the front portion, which may be arranged in a y-direction.

The front portion also includes a bending beam portion. The clamping element can cause a resilient deflection of the bending beam section by a clamping force. The deflection represents a change in shape of the bracket, which is caused by the tensioning of the clamping element. Initial state for determining the deflection is the force-free state, d. H. if the clamping element is not yet tensioned. The elastic deflection can thus be considered according to the known bar theory as a deviation of the course of the neutral fiber in the loaded state to the course in the unloaded state. This size can be called w and have the dimension of a length (unit meters). It is possible, according to the known beam theory, to introduce a bending line which corresponds to the neutral fiber of the component. The curvature w of the bending line is known to be proportional to the bending moment and inversely proportional to the axial moment of inertia of the component The deflection w can be obtained according to the beam theory by integrating the curvature twice along the length of the considered component, in this case the bending beam section.

The bracket may exert a force on the cover of the diode laser element in the power transmission section. This force can be effected by the tensioning of the tensioning element.

This force, which may occur as a result of the tensioning of the tension member, pushes the diode laser element onto the support member. By this pressure, a good heat transfer from the heat transfer surface can be achieved on the support element.

The joint may be designed as a pivot, which allows a change in angle between the base portion and the support portion. Such an angle change can occur due to the clamping force. This means that the angle between the base section and the Can change support section during clamping of the clamping element. As a reference, a centerline of the base portion and a centerline of the support portion may be used.

In a further advantageous embodiment, the joint may be designed as a support. The term support is understood in the sense of statics. In contrast to the restraint, only the location coordinate is specified for the support, not the direction of the bending line at the location of the bearing. A support is thus characterized in that no torques can be transmitted in this case with respect to an axis of rotation oriented in the direction y. The support can be designed as a fixed bearing or floating bearing. The support may be designed so that the base portion rests on the support portion. This edition may be punctiform, linear or flat.

The stirrup can transmit the force to the lid at at least one location, which is at a laser element height h _l is disposed above the heat discharge surface and the joint is disposed in a plane parallel to the heat discharge surface, which is at a joint height of at least 0.5 * h _l and at most 2 * h _l located above the heat delivery surface. The laser element height h _l may then be the height of the laser element from the heat delivery surface to the top of the lid. This laser element height can be measured in a side view (xz-plane) in the direction z. It may be advantageous to arrange the joint above the plane of the heat discharge surface to avoid lateral forces in the direction x during clamping of the clamping element. To determine the plane in which the joint is arranged, the position of the axis of rotation of the joint can be used. For this, the z-coordinate of the axis of rotation in the y-direction can be regarded as decisive.

The bending beam section may have a first taper relative to the base section. The bending beam section may have a second taper relative to the power transmission section. A taper can be understood as a reduction of the cross section with respect to a yz plane. The bending beam section can thus have a smaller width b and / or a lower height h than the base section and / or the power transmission section. As a result, it can be achieved that the deflection according to the invention occurs predominantly in the bending beam section, while the base section and / or the power transmission section experience no or only slight deflection when the tensioning element is tensioned. The width can be understood here as a spatial extent in the y-direction, the height as an extent in the z-direction.

The front portion may also include a rigid portion adjacent the base portion. The rigid section may itself adjoin the bending beam section. The rigid section experiences by the clamping force no significant deflection. A negligible deflection should be disregarded. As a negligible bending can be considered, which has at least three times the bending radius compared to the minimum bending radius in the bending beam section. The rigid portion may thus have a minimum bending radius which is at least three times as large as the minimum bending radius in the bending beam section. A rigid portion may be advantageous to avoid kinking of the bracket in the region of the approach surface of the clamping element. The rigid portion may have the same cross section with respect to yz planes as the base portion.

The bending beam section may have a first axial area moment of inertia and the base section a second axial area moment of inertia. The first axial area moment of inertia can advantageously be smaller than the second axial area moment of inertia. As a result, it can be achieved that the deflection occurs predominantly in the bending beam section, while the base section experiences no or a comparatively slight deflection. A reduction in the axial area moment of inertia in the bending beam section can be achieved in that the bending beam section has a smaller width, ie the spatial extent in the y direction and / or a smaller height, ie expansion in the z direction. The first axial surface moment of inertia can for example advantageously be chosen between 2 mm and 500 mm ^{4 4,} particularly advantageously between ⁴ and 20mm 200mm. ⁴

The bending beam section may have a first polar area moment of inertia and the base section a second polar area moment of inertia. The first polar area moment of inertia can advantageously be smaller than the second polar area moment of inertia. The bracket can thereby be provided such that the power transmission section can yield relative to the base section about an axis of rotation in the x direction. By means of such a torsion, the bow can yield slightly, if, for example, the upper cover surface is not completely parallel to the heat transfer surface due to production-related tolerances. Such wedge errors can then be compensated by a twist of the bracket preferably in the bending beam section. By in the proposed expression of the polar moments of inertia can be achieved that a possible torsion occurs predominantly in the bending beam section, while the base section no or one comparatively low torsion experiences. In addition, by reducing the polar area moment of inertia in the bending beam section, a more even distribution of the pressing force on the cover can be achieved even if there is a wedge error. A reduction in the polar area moment of inertia in the bending beam section can be achieved by virtue of the fact that the bending beam section has a smaller width, ie the spatial extent in the y direction and / or a smaller height, ie the extension in the z direction.

The reduction of the axial and / or polar area moment of inertia in the bending beam section can advantageously be achieved by the above-described narrowing of the bending beam section relative to the base section. It may be particularly advantageous to provide in the -x direction following the base section a rigid section which has the same cross-section as the base section. Subsequent to the rigid portion of the bending beam portion may be provided which has a relation to the rigid portion tapered cross-section. It should also be noted that the axial and polar area moments of inertia with respect to the neutral fiber are to be calculated, or can be converted accordingly with Steiner's theorem. For practical handling, it may in most cases be sufficiently accurate to relate the axial and polar area moments of inertia to the centroid areas.

It may be advantageous that the bracket is made in one piece. This means that the front portion, the base portion and the support portion made of a material-related material. The bracket may be L-shaped in the side view (xz-plane), wherein the long leg extends in the -x direction and includes the base portion and the front portion. The short leg may extend in the z-direction and comprise the support section. The joint can advantageously be designed as a solid-body joint. A solid-state joint may, in a known manner, have one or more weakenings of the material cross-section. A weakening of the material cross-section can be advantageously provided in the knee of the bracket. The knee of the stirrup is the point at which the base portion adjoins the support portion. For an L-shaped bracket, this may be the location where the two legs meet.

In a further likewise advantageous embodiment, a first part of the strap comprising the force transmission section, the bending beam section and the base section can be manufactured from a first piece. The support portion may be made of a second piece, which is not materially related to the first part. The first part of the bracket can rest on the support section in the area of the base section. The joint can then be advantageously designed in the manner described above as a support.

The bracket can advantageously consist of a metallic material. For example, stainless steel, steel or aluminum may be suitable. In order to avoid a short circuit, an electrically insulating intermediate layer can be provided between the carrier element and the heat-dissipating surface and / or between the cover and the force-transmitting section and / or between the support section and the carrier element. In other places, an electrical insulation can also be provided. For example, a screw can be electrically isolated as a clamping element with a Isolierbuchse opposite the bracket.

The bending beam portion may have a width b and a height h, wherein the ratio of the height h to the width b of the bending beam portion is a value between 1: 3 and 3: 1 having. For example, the bending beam section may advantageously have a width between 2 mm and 8 mm and a height between 2 mm and 8 mm. While known bracket made of sheet metal for clamping power transistors of the prior art with a height-to-width ratio of, for example 1:10 can apply only a small pressure, the said aspect ratio of the bending beam portion of the invention may prove to be particularly advantageous for attaching diode laser elements. A pressure force between 0.1 kN and 20 kN, particularly advantageously between 0.2 kN and 15 kN, is advantageous. Practically very particularly advantageous has a pressure between 0.5kN and 5kN proven. Although a constant cross-section of the flexbeam section over most of the length may be advantageous, the flexbeam section may also have a variable cross-section along the length (x direction).

The support portion can rest flat on the support element. But that does not necessarily have to be the case. In a further preferred embodiment, the support portion may rest linearly or punctiformly on the carrier element. A linear footrest can be accomplished, for example, by a rounded foot of the support section or by a bevelled foot, wherein the support section can rest on a foot edge on the support element. As a foot here is the lower portion of the support portion to understand, which can rest on the support member. A linear Fußauflager can be accomplished, for example, also by the fact that the bracket in the above manner consists of two parts, wherein the support portion like a roller, ie as a round rod or round rod portion is formed with the axis in the y-direction. Similarly, one can effect a punctiform Fußauflager by a spherical configuration of the support portion.

With regard to the x-coordinate, the footrest can be advanced relative to the axis of rotation of the joint in the direction of the laser element (-x direction). This can have the advantage that a transverse force in the x-direction can be compensated as a result of the deflection of the bracket and / or the restoring force of the joint. The bracket can therefore rest with its support portion with a point or linear Fußauflager on the support element. This support may be a direct support, or a spacer may be placed therebetween. The Fußauflager can be vorverlagert in a projection on a plane parallel to the heat dissipation surface with respect to the axis of rotation of the joint in the direction of the laser element (-x direction).

The solution according to the invention can be particularly advantageous if a plurality of diode laser elements are arranged side by side on a common carrier element. For each diode laser element, a bracket may be provided in each case. It may be advantageous if at least or exactly one clamping element is provided for each bracket. Then, namely, the diode laser elements can be attached independently. Of course, the support portions of a plurality of brackets may be formed as portions of a common contiguous portion, such as a round bar. However, the base sections and the front section as well as the clamping elements can advantageously be designed to be associated with exactly one diode laser element in each case.

The clamping element may have a thread with a pitch for the purpose of clamping. This can be for example a screw. The clamping element may also be formed as a threaded bolt, which is anchored for example in the support member and having a nut for clamping. The bracket undergoes an elastic deformation during clamping. The elastic deformation may be greater than a quarter of the thread pitch at the location of the threaded attachment surface. In an expert manner, the bending beam section can be suitably dimensioned for this purpose. This can ensure that the attachment of the diode laser element can not loosen, if it should come to a relaxation of the screw. The elastic deflection of the bending beam section may preferably be greater than 0.1 mm at the maximum. You can also express the deflection as the radius of curvature. The minimum radius of curvature of the stirrup can advantageously be less than 5 m, particularly advantageously less than 2 m. Practically as very particularly advantageous, a minimum radius of curvature between 0.1 m and 1 m has been found. The minimum radius of curvature can occur in the bending beam section. Advantageously, the bracket can be dimensioned so that the bending radius in the base portion and the rigid portion is at least twice as large as the minimum bending radius in the bending beam section. Advantageously, the bracket may be sized so that no deflection occurs in the support section.

1. a) Bereitstellen des Diodenlaserelements des Trägerelements und des Bügels,
2. b) Anordnen des Diodenlaserelements auf dem Trägerelement,
3. c) Bereitstellen eines Spannelements,
4. d) Spannen des Spannelements.

Furthermore, a method for fixing a diode laser element on a support element by means of a bracket is proposed. The diode laser element comprises at least one diode laser bar having at least a first contact area and a second contact area, a first heat conduction body which is thermally and electrically connected to the first contact area and has a heat dissipation area. The diode laser element further comprises a lid with a pressure surface. The bracket includes a front portion having a front edge, a base portion, and a support portion. The front portion includes a power transmission portion having a power transmission surface and a bending beam portion. Between the support portion and the base portion, a hinge is provided. Angle α is present between the force transmission surface and the pressure surface. The method according to the invention comprises the following steps:

1. a) providing the diode laser element of the carrier element and of the bracket,
2. b) arranging the diode laser element on the carrier element,
3. c) providing a tensioning element,
4. d) clamping the clamping element.

When clamping the clamping element occurs a deformation of the joint. The front edge of the bracket first presses on the lid. The diode laser element may be arranged so that the leading edge is at a location above the diode laser bar with respect to the direction of force -z. That is, in a projection in the z-direction, the leading edge represents a line that lies within or intersects the outline of the diode laser bar. During clamping, an elastic deflection of the bending beam section continues to occur. Along with the deflection of the bending beam section, the angle α changes. In this case, the clamping element can be stretched so strong that the angle α is zero. This means that the power transmission section no longer presses linearly on the pressure surface, but then rests flat on the lid.

The tensioned by a tensioner strap can be used to attach a diode laser element on a support, wherein the tensioning device has a thread with a pitch and the bracket undergoes a deformation during clamping, which is greater than a quarter of the thread pitch.

In this case, a plurality of brackets may be provided, wherein each bracket is associated with a clamping element and with each bracket a diode laser element is attached and the diode laser elements are arranged on the support side by side.

list of figures

• 1 zeigt ein erstes Ausführungsbeispiel;
• 2 zeigt das erste Ausführungsbeispiel;
• 3 zeigt das erste, ein zweites und ein drittes Ausführungsbeispiel;
• 4 zeigt einen ungespannten einteiligen Bügel eines vierten Ausführungsbeispiels;
• 5 zeigt den gespannten Bügel des vierten Ausführungsbeispiels;
• 6 zeigt ein fünftes Ausführungsbeispiel mit mehreren Laserelementen;
• 7 zeigt einen Bügel eines sechsten Ausführungsbeispiels;
• 8 zeigt einen Bügel eines siebenten Ausführungsbeispiels;
• 9 zeigt einen zweiteiligen Bügel eines achten Ausführungsbeispiels;
• 10 zeigt einen zweiteiligen Bügel eines neunten Ausführungsbeispiels;
• 11 zeigt einen einteiligen Bügel mit abgerundetem Fuß eines zehnten Ausführungsbeispiels;
• 12 zeigt einen einteiligen Bügel mit abgeschrägtem Fuß eines elften Ausführungsbeispiels;
• 13 zeigt ein zwölftes Ausführungsbeispiel;
• 14 zeigt ein dreizehntes Ausführungsbeispiel mit zwei Gelenken.

The figures show the following:

• 1 shows a first embodiment;
• 2 shows the first embodiment;
• 3 shows the first, a second and a third embodiment;
• 4 shows an unstressed one-piece bracket of a fourth embodiment;
• 5 shows the tensioned bracket of the fourth embodiment;
• 6 shows a fifth embodiment with multiple laser elements;
• 7 shows a bracket of a sixth embodiment;
• 8th shows a bracket of a seventh embodiment;
• 9 shows a two-part bracket of an eighth embodiment;
• 10 shows a two-part bracket of a ninth embodiment;
• 11 shows a one-piece bracket with rounded foot of a tenth embodiment;
• 12 shows a one-piece bracket with a tapered foot of an eleventh embodiment;
• 13 shows a twelfth embodiment;
• 14 shows a thirteenth embodiment with two joints.

A first embodiment of a laser module according to the invention 1 is in 1 in a side view (xz-plane) with viewing direction y and in 2 in a plan view (xy plane) with viewing direction -z shown. It is a diode laser element 3 on a support element 2 with a strap 4 clamped. The hanger is with a screw 5 clamped as a clamping element. As a result, the bracket presses with its power transmission section 16 with a force 29 on the lid 14 of the laser element. The support member is formed as a heat sink, wherein for the heat dissipation cooling channels (not shown) are provided in the interior of the support member. A coolant can via coolant connections 35 be added and removed. The bracket is L-shaped and has two legs, which have a joint 25 are connected, which is formed in this example as a solid-state joint. The shorter leg forms the support section 23 , which derives a supporting force in -z direction on the support element. The longer leg of the stirrup can be divided into a base section 22 extending from the hinge in the -y direction to the screw, and a subsequent front section 21 extending in -z direction beyond the screw to the diode laser element. The front section in turn can be subdivided into a rigid section 20 , a bending beam section 19 and the power transmission section 16 , In the side view in 1 the long leg is bent by the clamping force of the screw. In the plan view in 2 you see a first rejuvenation 30 ie a reduction in the width of the stirrup from the rigid section 20 to the bending beam section 19 , You can also see a second rejuvenation 31 ie a reduction in the width of the bracket from the power transmission section 16 to the bending beam section 19 ,

In 3 is the laser module 1 of the first embodiment shown in the side view prior to assembly. The longer horizontal leg of the strap 4 with the base section 22 and the front section 21 , is not bent before assembly. The screw 5 is with a washer 6 Afterwards, the clamping force of the screw on the clamping element attachment surface 24 of the temple 4 transfers.

The diode laser element 3 consists of a diode laser bar 8th , a first heat-conducting body 11 and a lid 14 , which outside of the laser bar, in this case behind the laser bar, via an electrically insulating joint layer 13 is connected to the first heat conducting body. In this case, the laser bar has a first contact surface 9 and a second contact surface 10. The first contact surface is electrically connected to the first heat conducting body and the second contact surface is connected to the lid. In addition, a temperature sensor (not shown) may be attached to the diode laser element. the diode laser element has a heat dissipation surface 12 on which the underside of the first Wärmeleitkörpers 11 is. This heat transfer surface is over an interposed electrical insulation layer 36 on the carrier element 2 placed. As the electrical insulation layer, a heat conducting film is used in this case. In a modification of the first embodiment is the diode laser element is placed directly on the support element without interposed heat conducting foil. The lid 14 has a printing surface 15 which is located on the top of the lid and is intended to receive the pressing force of the bracket. The bracket has to a power transmission surface 18 on, which is at the bottom of the power transmission section 16 located. Between the pressure surface and the force transmission surface is an electrical insulation layer 36 provided, of course, can be omitted if no electrical insulation of the lid is required to the bracket. In the first embodiment, no spacer is present (37 not equipped).

In a second also in 3 illustrated embodiment is a spacer 37 provided, which between the foot 32 of the support section 23 of the temple 4 and the carrier element 2 is introduced in order to raise the bracket raised by the height of the spacer can. In this way, the bracket can be operated with a higher clamping force without the support section would have to be extended.

In a third embodiment, the spacer 37 designed electrically insulating. The washer 6 is electrically insulating designed as insulating bushing. The bracket is with the power transmission surface 18 without electrically insulating layer directly on the printing surface 15 the lid placed so that the bracket for supplying the operating current to the lid of the diode laser element can be used.

Based 4 and 5 the method according to the invention is illustrated in a fourth embodiment. In 4 is the provided strap 4 shown. In the support section 23 is an imaginary midline 40 located. In the horizontal longer thigh is a center line 38 which will later represent the bending line. The joint 25 is designed as a solid-body joint. There are two weak points for this purpose 26 made of material cross section, which can be bent with a small force. In the illustrated embodiment, the hinge may be assumed to be a hinge about a y-direction. The axis of rotation can be approximately at the intersection of the lines 38 and 40 be accepted. More precisely, the position of the axis of rotation can be determined by a FEM simulation of the solid-state joint. The transmission area 18 has a leading edge 17 on.

5 now shows the with a clamping force 7 tense strap 4 , For clarity, the clamping element (screw) is not shown, but only the clamping force. When tightening the clamping element, the bracket will initially yield in the joint, so that the angle between the long leg and the short leg changes. The base section 22 So it turns against the support section 23 in the axis of rotation of the joint 25 , This sets first the leading edge 17 of the strap on the lid 14 of the laser element 3 on. The placement of the front edge 17 works here because the joint 25 at a greater height above the support element 2 is arranged as the height of the laser element h _l , Until touchdown is the bending beam section 19 not yet bent. Upon further tightening, the bending beam section is now deflected and the joint continues to rotate. The deflection is made by an auxiliary straight line 39 illustrated in the base section parallel to the bending line 38 is drawn. The further tightening is accompanied by a reduction in the angle α between the force transmission surface and the pressure surface. You can stretch the bracket so far that the power transmission surface comes to lie flat on the printing surface. On the other hand, if one does not stretch the yoke quite so far, one can create a linear force entry into the diode laser element 3 at the front edge 17 effect of the temple. The leading edge 17 is in the -z direction above the laser bar 8th , This can be advantageous because it can thereby prevent a beak-like rising of the laser element, in which the lid can lift off the laser bar in the front region.

6 shows as a fifth embodiment, a laser module 1 in which a plurality of diode laser elements 3 on a common carrier element 2 are attached. Each diode laser element 3 is a strap 4 assigned. Every hanger 4 is each a screw 5 assigned as a clamping element.

7 shows a sixth embodiment, in which the bending beam section 19 has a variable in the z direction cross-section.

8th shows a seventh embodiment in which the entire front portion 21 and the base section 22 have a same constant width (extension in the y direction).

9 shows an eighth embodiment, in which the support portion 23 is designed as a second part in the form of a round rod. The joint is as a support 27 educated. The clamping element is designed here as a threaded bolt and is clamped with a nut. Threaded bolt and nut form the clamping element here 5 , In a modification of the eighth embodiment is as a support portion 23 provided a ball.

10 shows a ninth embodiment, wherein the support portion is a linear support 33 has on the support element. This is a rounded foot 33 intended.

11 shows a tenth embodiment. The joint 25 is here as a solid-state joint with two vulnerabilities 26 formed of the material cross-section. The support section has a linear support 33 on the carrier element. For this purpose, a rounded foot is provided, which can also be considered as a second joint. The footrest 33 however, it is not necessarily used as a hinge here. It serves primarily to avoid an over-determined areal support of the support portion on the support element.

12 shows an eleventh embodiment with a bevelled foot 34 the support portion which rests on a foot edge on the support element. The footrest 34 is linear. The joint 25 is designed as a solid-body joint and has a weak spot 26 of the material cross section. The rotation axis 28 of the joint 25 can be assumed approximately in the middle of the weakened material cross-section parallel to the y-direction. Regarding the x-coordinate, the footrest is 34 relative to the axis of rotation of the joint in the direction of the laser element (-x direction) vorverlagert. This support is a direct support, in a modification of this embodiment, a spacer may be interposed therebetween. The footrest 34 Thus, in a projection on a plane parallel to the heat dissipation surface (ie in a projection on an xy plane) relative to the axis of rotation 28 the joint in -x direction, ie in the direction of the laser element not shown here or in the direction of the power transmission section 16 be relocated.

13 shows a twelfth embodiment with a pyramidal support portion 23 ,

14 shows a thirteenth embodiment with a support portion 23 which is designed as a ball.

LIST OF REFERENCE NUMBERS

1.

Device for emitting laser radiation (laser module)

Second

support element

Third

diode element

4th

hanger

5th

Clamping element, screw

6th

washer

7th

tension

8th.

diode laser bars

9th

first contact surface

10th

second contact surface

11th

first heat-conducting body

12th

Heat transfer surface

13th

electrically insulating joining agent layer

14th

cover

15th

print area

16th

Power transmission section

17th

leading edge

18th

Force transmission surface

19th

Bending beam section

20th

rigid section

21st

front section

22nd

base section

23rd

support section

24th

Clamping element approach surface

25th

Joint, solid body joint

26th

Weak point of the material cross-section

27th

Joint, designed as a support

28th

Axis of rotation of the joint

29th

force

30th

first rejuvenation

31st

second rejuvenation

32nd

Foot of the support section

33rd

linear foot rest with rounded foot

34th

linear footrest by bevelled foot with foot edge

35th

Coolant connection

36th

electrical insulation layer

37th

spacer

38th

elastic line

39th

auxiliary straight

40th

Centerline of the support section

Claims (17)

Laser module (1), comprising a carrier element (2), a diode laser element (3), a bracket (4) and a clamping element (5), wherein the diode laser element (3) comprises at least one diode laser bar (8) with at least one first contact surface (9). and a second contact surface (10), a first heat conducting body (11), which is thermally and electrically connected to the first contact surface and has a heat discharge surface (12), and a lid (13), wherein the bracket comprises a front portion (21), a base portion (22), and a support portion (23), the front portion including a power transmission portion (16) and a bending beam portion (19) and a hinge between the support portion and the base portion (22) (25 or 27) is provided, wherein the bending beam portion (19) relative to the base portion (22) has a first taper (30) and / or the bending beam portion (19) relative to the power transmission portion has a second taper (31), and the clamping element (5) by a clamping force (7) causes an elastic deflection of the bending beam portion (19) and the bracket in the power transmission portion exerts a force (29) on the cover of the diode laser element and the force (29) presses the diode laser element on the carrier element (2). Laser module after Claim 1 , characterized in that the hinge is designed as a hinge (25) which permits a change in angle between the base portion (22) and the support portion and / or that the hinge is designed as a support (27) of the base portion on the support portion. Laser module according to one of the preceding claims, characterized in that the bracket transmits the force to the cover at at least one location, which is arranged in a laser element height h _L above the heat delivery surface and the joint is arranged in a plane parallel to the heat transfer surface, located in a joint height of at least 0.5 * h _L and at most 2 * h _L above the heat transfer surface. Laser module according to one of the preceding claims, characterized in that the front portion also has a rigid portion (20) adjacent to the base portion (22), which in turn adjoins the bending beam portion (19), the rigid portion undergoing no substantial deflection. Laser module according to one of the preceding claims, characterized in that the bending beam section (19) has a first axial and a first polar area moment of inertia and the base section (22) has a second axial and a second polar area moment of inertia, the first axial area moment of inertia being smaller than the second axial area moment of inertia and / or the first polar area moment of inertia is smaller than the second polar area moment of inertia. Laser module according to one of the preceding claims, characterized in that the bracket is made of one piece and / or that the joint is designed as a solid-body joint (25). Laser module according to one of the aforementioned Claims 1 to 5 characterized in that a first part of the bracket comprising the power transmission portion (16), the bending beam portion (19) and the base portion (22) is made of a first piece, and the support portion (23) is made of a second piece and the first one Part of the bracket in the region of the base portion rests on the support portion. Laser module according to one of the preceding claims, characterized in that the bracket consists of a metallic material. Laser module according to one of the preceding claims, characterized in that the bending beam section (19) has a width b and a height h, wherein a ratio of the height h to the width b of the bending beam section has a value between 1: 3 and 3: 1. Laser module according to one of the preceding claims, characterized in that the support section rests linearly (32) or punctiform on the carrier element. Laser module according to one of the preceding claims, characterized in that the diode laser bar is connected to the second contact surface areally with the cover and / or the cover is connected via an electrically insulating joining agent layer (13) areally with the first heat conducting body. Laser module according to one of the preceding claims, characterized in that a plurality of diode laser elements are arranged side by side on a common carrier element, wherein for each diode laser element in each case a bracket is provided and that for each bracket at least or exactly one clamping element is provided. Laser module according to one of the preceding claims, characterized in that the clamping element for the purpose of clamping a thread with a pitch and the bracket undergoes an elastic deformation during clamping and the elastic deformation at the location of the threaded approach surface is greater than a quarter of the thread pitch and / or the elastic deflection of the bending beam section is greater than 0.1 mm at maximum and / or the minimum bending radius in the bending beam section is less than 2 m. Laser module according to one of the preceding claims, characterized in that the bracket with a point or linear foot rest 34 on the support element directly or via a Spacer rests, the Fußauflager 34 is projected in a projection on a plane parallel to the heat transfer surface relative to the axis of rotation (28) of the joint (25) in the direction of the laser element. Method for fixing a diode laser element (3) on a carrier element (2) by means of a yoke (4), wherein the diode laser element comprises at least one diode laser bar (8) with at least one first contact surface (9) and a second contact surface (10), a first heat conducting body (8) 11) thermally and electrically connected to the first contact surface and having a heat dissipation surface (12), and a lid (13) having a pressure surface (15), and wherein the bracket includes a front portion having a front edge (17), a base portion (22), and a support portion (23), the front portion including a power transmission portion (16) having a power transmission surface (18) and a flexure beam portion (19), the flexure beam portion (19) relative to the base portion (22) has a first taper (30) and / or the bending beam portion (19) opposite the power transmission portion has a second taper (31) and between the support portion and the base portion a hinge (25) is provided wherein there is an angle α between the front portion and the normal of the pressure surface, comprising the following steps a) providing the diode laser element (3) of the carrier element (2) and of the bracket (4) b) arranging the diode laser element on the carrier element c) providing a tensioning element (5), d) tensioning of the tensioning element, wherein during the tensioning of the tensioning element a deformation of the joint occurs, the front edge of the strap first presses on the cover, and during tensioning further an elastic deflection of the bending beam portion (19) occurs, and in conjunction with the deflection of the bending beam portion (FIG. 19) the angle α changed. Use of a clamping device clamped on a bracket for mounting a diode laser element, wherein the bracket comprises a front portion (21), a base portion (22), and a support portion (23), wherein the front portion of a power transmission portion (16) and a bending beam portion ( 19) and between the support portion and the base portion (22) is provided a hinge (25 or 27), wherein the bending beam portion (19) relative to the base portion (22) has a first taper (30) and / or the bending beam portion (19 ) has a second taper (31) opposite the power transmission portion, the tensioning device being threaded with a pitch and the bracket experiencing a distortion during tensioning which is greater than a quarter of the thread pitch. Use after Claim 16 , characterized in that a plurality of brackets are provided, wherein each bracket is associated with a clamping element and with each bracket a diode laser element is attached and the diode laser elements are arranged on the support side by side.

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