Method and apparatus for illuminating and optionally imaging surface

Abstract

The invention relates to a method for illuminating a surface area (11) which lies in an illumination plane (12) and which is to be illuminated by at least one light spot (5) of illumination radiation shaped in the illumination plane (12), comprising the following steps: providing the illumination radiation along an illumination beam path (2) and shaping the illumination radiation, and a light spot (5) is generated in the illumination plane (12). According to the invention, the method is characterized in that each affected spot (5) has a polygonal shape, the contour of which has a plurality of straight sections (BG). The intensity of the shaped illumination radiation is in the form of a top-hat distribution over the polygonal shape. Furthermore, light spots (5) are generated, each light spot (5) having one of the straight sections (BG) adjoining one another in the illumination plane (12). The invention also relates to a device for carrying out the method according to the invention.

Description

Technical Field

[0001] The invention relates to a method and a device according to the preamble of the main claim or of the coordinated claim. Background Art

[0002] In order to reproduce a larger portion of a sample, whether a biological object or an object, for example, from the field of construction components or material development, as an image, a plurality of partial images, also called tiles, can be acquired and stitched together to form a resulting image.

[0003] If the tiles are acquired at high resolution, the size of the tiles is correspondingly small. In order to be able to effectively stitch the tiles into the resulting image, they should have matching boundaries, in particular straight boundaries. Another requirement is to evenly illuminate the corresponding tiles. If the area of ​​the sample to be imaged as a tile, in particular the area of ​​the sample in the illumination plane, is illuminated with an illumination radiation having a Gaussian distribution of its intensity values ​​in the illumination plane, each tile shows a clear edge light drop. In order to reduce this effect, the individual tiles can be acquired with a large mutual overlap. The purpose here is to basically use only the dense part of the Gaussian illumination, so as to achieve uniform illumination. However, the time required for image acquisition increases in the process, and the sample may potentially be damaged due to repeated illumination and poor utilization of available light output. This can occur, for example, in biological samples, in the use of photosensitive dyes (fluorophores) and / or in photosensitive materials. Summary of the invention

[0004] The object of the invention is to propose a possibility for efficient imaging with the aid of a plurality of partial images which allows high-resolution image data and even illumination of the partial images.

[0005] This object is achieved by the subject matter described below. Advantageous improvements are also found below.

[0006] The present invention provides a method for illuminating a surface area, which surface area is located in an illumination plane and is to be illuminated by at least one spot of illumination radiation shaped in the illumination plane, the method comprising the following steps: providing illumination radiation along an illumination beam path; shaping the illumination radiation and generating the spots in the illumination plane; each affected spot has a polygonal shape, whose outline has a plurality of straight segments; wherein the intensity of the shaped illumination radiation is shaped into a top hat distribution by the polygonal shape; and the spots are generated such that corresponding ones of their straight segments are adjacent to each other in the illumination plane.

[0007] In one embodiment, the surface area to be illuminated is scanned with a plurality of light spots generated and adjoining one another.

[0008] In one embodiment, the polygonal shape of the light spot is a hexagon, a heptagon, an octagon or a decagon.

[0009] In one embodiment, the areas of the surface areas respectively illuminated by mutually adjacent light spots overlap by at most 10%, preferably at most 5%, of their total surface area.

[0010] In one embodiment, measured values ​​are in each case acquired from a region of the surface region illuminated by the light spot by detection radiation, which is caused by the illumination radiation, which is acquired as the measured value and stored as assigned to the respective light spot.

[0011] In one embodiment, the stored measured values ​​are combined by using the measured values ​​according to the spatial position of the respective light spot to form an image as individual image data and the stored measured values ​​are arranged next to each other in the correct position and orientation.

[0012] The present invention also provides a device for illuminating a surface area, which is located in an illumination plane and is illuminated by at least one light spot of illumination radiation shaped in the illumination plane, the device comprising: a light source for providing the illumination radiation; a beam shaping optical unit arranged in the illumination beam path downstream of the light source, for shaping the illumination radiation; a beam deflecting device and / or holding device with controlled sliding, on which the surface area to be illuminated is held; the beam shaping optical unit is designed to generate a light spot having a polygonal shape in the illumination plane, wherein the intensity of the shaped illumination radiation is formed in the form of a top hat distribution over the range of the light spot; and using an existing controller, generating light spots, each of which has straight sections of its contour adjacent to each other in the illumination plane.

[0013] In one embodiment, for shaping the illuminating radiation, at least one beam-limiting optical element is arranged in the illuminating beam path, which serves to direct only a portion of the illuminating radiation to the surface area to be illuminated, where the light spot is generated.

[0014] In one embodiment, at least one optical element is arranged in the illumination beam path, and the at least one optical element is used to split the illumination radiation into a plurality of partial beams; there is at least one optically effective element, by means of which at least some of the partial beams are combined and optionally superimposed on each other.

[0015] In one embodiment, at least one optical element is present in the illumination beam path for redistributing light of the illumination radiation within the illumination beam path, and a light spot with a top-hat distribution of the desired polygonal shape and the intensity is present at the end of the illumination beam path.

[0016] In one embodiment, the optical element is a spatial light modulator or a diffractive optical element.

[0017] In one embodiment, the optical element is a grating.

[0018] In a method for illuminating a surface area to be illuminated and optionally to be imaged, the surface area to be illuminated and optionally to be imaged is illuminated with at least one spot of illumination radiation. Here, the spot is generated in an illumination plane in which the surface area is located. Reference is made to the illumination plane below. The method comprises the steps of providing illumination radiation, shaping the illumination radiation, and generating the spot in the illumination plane. The illumination radiation is guided from a light source to the illumination plane along an illumination beam path.

[0019] For example, the surface area may be a part of a body surface.In further embodiments of the method, the surface area may also be located within the body or be coated by another material.

[0020] The method according to the invention is characterized in that each light spot achieved has a polygonal shape (cross section of the light beam). This means that light spots are generated in the illumination plane, wherein each light spot illuminates a surface area shape having a plurality of corner points. In addition, the intensity of the illumination radiation within the light spot, i.e. the cross section of the illumination radiation shaped when incident on the illumination plane, has the shape of a top hat distribution. A possible process for producing a top hat distribution of light spots is further explained below in conjunction with the device-side design of the invention. Laser radiation is advantageously used as illumination radiation. It is directed onto the surface area as wide-field illumination.

[0021] For example, a top hat distribution has only small fluctuations in intensity values ​​between its sharply falling edge regions (eg less than 10% of the intensity values, in particular less than 5% of the intensity values).

[0022] The contour of the polygonal light spot thus has a plurality of straight segments (from now on also: illumination boundaries), wherein the light spots are generated in the illumination plane, adjoining one another, in each case with one of their illumination boundaries. The generated light spots thus adjoin one another with at least one straight segment. If the light spots are not generated simultaneously, but with a (sequential) time shift, the light spots actually adjoin one another when observing the position and contour of the respective straight segments.

[0023] Mutually adjacent light spots are understood to mean those light spots in which the actual or virtual contours of the relevant illumination boundaries are in direct spatial contact or in which their respective illumination areas in the illumination plane overlap by at most 10%, better by at most 9%, 8%, 7% or 6%, preferably by at most 5% or 4% of their total surface area. This enables efficient image acquisition due to the absence or minimal overlap.

[0024] Advantageously, the surface area to be illuminated and optionally to be imaged is scanned with a plurality of generated and mutually adjacent light spots. The scanning can be performed by changing the relative positions of the surface area to be imaged and the spots in a time-controlled manner. The surface area can be scanned sequentially by successively illuminating and scanning the surface area with at least one light spot.

[0025] In another configuration of the method according to the invention, a portion of the surface area to be imaged can be covered simultaneously by a plurality of mutually adjacent spots. For this purpose, a plurality of light spots with corresponding relative positions to one another are generated simultaneously. By correspondingly shifting the positions of the plurality of spots on the surface area, a complete illumination of the surface area can be achieved.

[0026] In an advantageous configuration of the method according to the invention, the polygonal surface area of ​​the light spot is a hexagon, an octagon or a decagon. The polygon is advantageously regular here. The latter simplifies its generation and the stringing together of the light spots during the scanning of the surface area.

[0027] On the one hand, the polygon provides the desired rectilinear illumination boundary. On the other hand, such a polygon covers a relatively large field of view, as will be briefly explained below. A large field of view advantageously reduces the number of partial images (tiles) required for the image.

[0028] The maximum field number of the microscope is determined, for example, by the circular opening of the objective lens used. Here, the polygonal surface area of ​​the spot cannot completely fill the circular shape. However, the increase in the number of corners of the polygon is getting closer and closer to the circular shape. Therefore, for example, a polygon in the form of a square covers a part of about 0.67 of a circle, and the outer boundary of the circle passes through the corner points of the square. A polygon in the form of a hexagon has already filled a part of about 0.87 of the corresponding circle. The generation of spots in the form of octagons or decagons allows even greater filling of the circular surface area used here as a reference. The configuration of the polygonal surface area in the form of a hexagon has been shown to be a technically well-realized compromise between the generation of a sufficiently clearly defined edge (illumination boundary) of a high degree of filling and a corresponding spot, and is therefore an advantageous configuration of the present invention.

[0029] In order to generate an image of the illuminated area of ​​the surface area in another configuration of the method according to the invention, measured values ​​of an area of ​​the surface area illuminated by the light spot are recorded in each case. In this case, detection radiation caused by the influence of the illumination radiation is detected by a suitable detector. Here, the detection radiation can be fluorescent radiation excited by the illumination radiation and / or a reflected component of the illumination radiation.

[0030] Advantageously, the corresponding measured values ​​are stored, assigned to the corresponding light spot and its position and spatial extent on the surface area, and saved for further evaluation. The position and extent are preferably detected and specified in the transverse direction of the illumination beam path (x direction, y direction). Optionally, the position in the direction of the illumination beam path (z direction) can also be additionally detected and stored.

[0031] By using the measured values ​​as image data according to the spatial position of each light spot, the stored measured values ​​of the light spots, which can also be called the origin of the detected radiation, can be combined to form an image, and the stored measured values ​​of the light spots can be combined with the correct position and location.

[0032] The object of the present invention is also achieved by a device for illuminating a surface area to be illuminated. The device comprises a light source for providing illumination radiation, such as a laser light source, an LED or a halogen lamp. A beam shaping optical unit is arranged in the illumination beam path downstream of the light source, the beam shaping optical unit being used to shape the illumination radiation and thus for generating at least one shaped light spot in the illumination plane. In addition, there is a beam deflection device and / or a holding device with controlled sliding, on which the surface area to be illuminated is held. The beam deflection device can be, for example, a reflector, a micro-mirror array, etc. that can be pivoted in a controlled manner. The holding device can be realized, for example, by a controllable sample stage. The beam deflection device and / or the holding device in combination with a controller allow the absolute position of the light spot and its relative position on the surface to be illuminated to be accurately determined.

[0033] According to the invention, the device is characterized in that the beam shaping optical unit is designed to generate a light spot with a polygonal cross section in the illumination plane. Furthermore, on the polygonal cross section of the illumination radiation in the illumination plane, an intensity of the shaped illumination radiation in the form of a top hat distribution is provided by the action of the beam shaping optical unit, which can be composed of a plurality of interacting elements. In particular, as described above, by using a controller, the light spots are generated in the illumination plane so as to adjoin each other with corresponding illumination boundaries. For this purpose, the beam deflection device and / or the holding device can be controlled by means of the controller and a corresponding relative movement can be generated.

[0034] In a possible embodiment, the device according to the invention can have at least one beam-limiting optical element for shaping the illumination radiation in the illumination beam path and / or for generating a top-hat distribution within the scope of the light spot in the illumination plane. Due to the effect of the beam-limiting optical element, only the components of the illumination radiation (more precisely: those illumination beams) which generate the light spot there are guided to the surface area to be illuminated.

[0035] Thus, for example, a diffractive, refractive or reflective element can be used to "cut out" a spot of desired shape from the provided illumination radiation. Such an element can be, for example, a suitably designed aperture. Furthermore, desired or undesired components of the illumination radiation can be spatially separated from one another, for example by means of a wedge-shaped phase of the element. A uniform distribution of the intensity can be improved by spatially adapting the wedge-shaped phase pattern, i.e. the element area causing the phase shift, to the spot to be shaped. In the process, components of the illumination radiation are lost. Furthermore, the shape of the illumination radiation must be known.

[0036] In another concept for generating a desired top-hat distribution, at least one optical element is arranged in the illumination beam path, which serves to split the illumination radiation into a plurality of partial beams. There is at least one optically active element, which serves to recombine at least some of the partial beams and optionally superimpose them on one another. In a particular embodiment, the optical element and the optically active element may be the same component, which may be the case, for example, of a light-conducting fiber or a rod.

[0037] One possible embodiment involves superimposing the partial light beams again in a smaller surface area by means of a focusing optical unit. This is possible, for example, using a microlens array as an optical element in combination with an optically active element for superimposing the partial light beams. The shape of the illumination radiation in the illumination plane is defined, for example, by the shape of the microlenses.

[0038] Reflective optical elements can also be used. For example, a reflector or a reflector array assumes the function of a microlens array. Here, the shape of the (micro) reflector substantially determines the resulting shape of the light spot.

[0039] Beam shaping can also be achieved in multimode fibers or light-guiding rods by exciting various spatial modes of input coupled light in the light-guiding fiber or rod. By mode mixing, a uniform beam profile can be generated at the end of the fiber or rod. The shape of the cross section of the fiber or rod represents the achieved beam shape. As a result of the superposition of modes, a beam profile with small-scale, usually interference-related intensity fluctuations (speckle) is generated. In addition, the light at the end of the fiber or rod is spatially incoherent. Speckle can be reduced by, for example, setting the fiber or rod to mechanical vibration or by placing a movable diffuser plate in the beam path.

[0040] In another possible embodiment, if at least one optical element is introduced into the illumination beam path, through the action of the optical element, the light of the illumination radiation is redistributed within the illumination beam path, and there is a light spot with a top-hat distribution having a desired polygonal surface and intensity at the end of the illumination beam path, which is referred to herein as the principle of beam redistribution.

[0041] In this case, the intensity distribution of the initially present Gaussian illumination radiation is redistributed with the aid of an optical unit in such a way that the desired beam shape and the desired intensity distribution in the illumination plane result. In order to achieve beam shaping by redistributing the intensity, the initial beam shape must be known. If only homogenization is performed, the input beam shape is no longer important.

[0042] In order to generate such a beam redistribution, for example a diffractive optical element (DOE) can be arranged in the illumination beam path. Likewise, there can be a spatial light modulator (SLM, for example in the form of LCOS [liquid crystal on silicon] or DMD [digital mirror device]) or a refractive optical unit, for example a corresponding optical lens.

[0043] The diffractive optical unit can be used for transmission (e.g. transmission SLM, transmission DOE) or reflection, for example as a liquid crystal on silicon SLM (LCOS-SLM) or as a reflective DOE. In order to transform a Gaussian beam according to the requirements of the present invention, a phase function must be determined, which is implemented, for example, with the aid of a DOE or SLM. For example, the Gerchberg-Saxton (GS) algorithm can be used to determine such a phase function. However, a disadvantage of this algorithm is that the phase after beam shaping is not flat, but chaotic. Correction of the phase can be accomplished via a second phase element in the conjugate Fourier plane, as described, for example, in the article by Jesacher et al. (Jesacher, A. et al., 2008: Near-perfect hologram reconstruction with a spatial light modulator. OPTICS EXPRESS 16 (4): 2597-2603).

[0044] Another option is to generate and use holograms, for example in so-called computer-generated holograms (CGH) of the illumination radiation in the pupil, where a phase is impressed which, after a subsequent Fourier transformation, leads to the desired intensity distribution in the intermediate image.

[0045] Another possibility for providing a top-hat profile of the intensity distribution is the generalized phase contrast (GPC) method. For this purpose, a phase pattern of the image to be imaged is generated in the intermediate image. A so-called common path interferometer is produced by installing a rectangular or circular phase mask (phase contrast filter) with a pi phase deviation for the low spatial frequencies in the pupil. The intensity distribution of the image to be imaged is recovered from the interference of the phase-shifted low spatial frequencies and the unmodulated higher spatial frequencies.

[0046] In a further embodiment, the beam shaper can be integrated in or mounted on a single mode fiber. The integration of a beam shaper in or on a single mode fiber can be achieved, for example, by 3D printing refractive or diffractive optical elements or nanostructures or metamaterials directly on the fiber end. In addition to the beam shaper, spherical and aspherical optical elements for collimation can also be printed. With this beam shaping technology, it is also possible to shape a uniform and spatially coherent beam.

[0047] If the beam shaper is printed on a multimode fiber, any desired beam shape can still be generated, but the spatial coherence is limited. Additionally or alternatively, a multimode fiber with a polygonal cross-section (e.g., with a pentagonal, hexagonal, heptagonal, or octagonal cross-section) can be used to achieve a top-hat distribution.

[0048] Further technical solutions are provided by using arrays of gratings, prisms or mirror elements.

[0049] Arrays of gratings, prisms or mirrors can be used to shape and homogenize partially coherent light (e.g., LEDs) as desired. Similar to a microlens array, the incident beam is split by the array and the output in the illumination plane is rearranged to produce the desired beam shape.

[0050] The spatial coherence of the shaped and homogenized light beam is applied, for example, in microscopy applications using structured illumination microscopy (SIM).For this purpose, for example, a grating is illuminated and imaged into the illumination plane.

[0051] If a diffuser is used in the illumination beam path, it leads to a non-deterministic redistribution and thus to a homogenization of the light. The beam is then shaped by cutting the beam (see above), for example with the aid of a stop.

[0052] The advantages of the present invention are uniform illumination of individual light spots without undesired edge light drop, and also efficient scanning or occupation of the surface area to be illuminated. The present invention can be used for illumination beam paths for both transmitted light illumination and incident light illumination. Furthermore, the present invention can be mounted on upright and inverted stands. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The invention will be explained in more detail below based on exemplary embodiments and with reference to the accompanying drawings, in which:

[0054] Figure 1 shows a schematic diagram of an illumination beam path with beam integration;

[0055] Figure 2 shows a schematic diagram of an illumination beam path with beam redistribution;

[0056] Figure 3 A schematic diagram of an exemplary embodiment of a microscope is shown with a direct image representation of the fiber optic output of a light source;

[0057] Figure 4 shows a schematic diagram of a second exemplary embodiment of a microscope with a light source and an upstream diffuser plate and diaphragm;

[0058] Figure 5 shows a schematic diagram of a third exemplary embodiment of a microscope with a computer-generated hologram and beam shaping;

[0059] Figure 6 A schematic diagram showing a surface area to be illuminated and two light spots generated in a top view; and

[0060] Figure 7 A schematic diagram showing a surface area scanned by multiple light spots is shown in a top view. DETAILED DESCRIPTION

[0061] In the following figures and exemplary embodiments, identical reference numerals denote equivalent technical elements unless otherwise stated.The simplified illustration of the individual optical lenses 3 also encompasses possible more complex optical arrangements.

[0062] exist Figure 1 In the simplified illustration of an illumination beam path 2 of FIG. 1 , the principle of so-called beam integration is explained using an example. Starting from a light source 1 , which in particular provides a laser, the illumination radiation is guided along the optical axis oA of the illumination beam path 2 and to a microlens array 4 by means of an optical lens 3. Due to the influence of the individual microlenses, the illumination radiation is divided into partial beams 2T. For a better overview, two of the partial beams 2T are represented as examples and highlighted with shading. The partial beams 2T are superimposed in the illumination plane 12 by means of at least one suitable optical lens 3, so that a light spot 5 of a specific shape and intensity distribution is achieved there. According to the invention, a light spot 5 with a polygonal shape and a top-hat distribution of its intensity (shown by a pictogram) is generated.

[0063] Figure 2The principle of beam redistribution is shown. Starting from a light source 1, the illumination radiation travels to an optical unit 3, which serves to redistribute the intensity, which initially has a Gaussian distribution (see pictogram), within the illumination beam path 2. With the aid of a further optical unit 3, the illumination radiation thus shaped is, for example, parallel and optionally the cross section of the illumination radiation is given a polygonal shape. The shaped illumination radiation has a top-hat distribution of its intensity (see pictogram).

[0064] In the context of the present invention, the illuminating radiation can be brought to the surface area 11 of the sample 10 to be illuminated in various ways. Figure 3 In the exemplary embodiment of the microscope M, the illumination radiation of the light source 1 is coupled into a light-conducting fiber 7, in particular in the form of a multimode fiber, by means of a corresponding coupling optical unit 6. The ends of the light-conducting fiber 7 have a polygonal cross section or an end in a beam shaper, which serves to shape the cross section of the illumination radiation. The illumination radiation that exits divergently at the fiber output is imaged by means of an optical lens 3 or a more complex optical unit 3 as well as a tube lens 18 and an objective 9 into an illumination plane 12, in which a surface area 11 of a sample 10 to be illuminated is arranged. The optical unit 3 is tuned here in such a way that, in combination with the tube lens 18, the diameter of the illumination radiation can be adapted. The sample 10 is located on a sample stage 13, which can be moved and controlled in a plane transverse to the optical axis oA by means of at least one drive 14.

[0065] By means of the controller 15, the light source 1, the driver 14 and optionally the optical lens 3 and the objective lens 9 can be optionally controlled. In addition, there is an evaluation unit 16, which is realized by a computer, for example, and which optionally serves as a display for communicating with a user and / or for displaying the recorded measured values ​​as image data. For this purpose, the controller 15 and / or the evaluation unit 16 are appropriately connected to a detector 19 for exchanging data.

[0066] The detection radiation caused by the light spot 5 on the surface area 11 is collected by means of the objective 9 and guided via an optical lens, for example a tube lens 18, along a detection beam path 17 to a detector 19, where the incident detection radiation is detected and stored as a measured value assigned to the position of the respective light spot 5. The required data memory can also be a separate technical unit or part of the controller 15 or the evaluation unit 16.

[0067] The separation of illumination radiation and detection radiation is achieved by means of a beam splitter 8, which is reflective for the illumination radiation and transmissive for the detection radiation. In other embodiments, the reflective or transmissive effect of the beam splitter 8 can also be achieved in the opposite way. The illumination beam path 2 and the detection beam path 17 are then arranged accordingly relative to each other.

[0068] A second exemplary embodiment of the microscope M has a diffuser plate 20 and a diaphragm 21 upstream of the light source 1 ( Figure 4 ). The light source 1 can be designed as a (laser) LED. The diffuser 20 serves to homogenize the intensity over the beam cross section, while the aperture 21 allows only a portion of the illumination radiation to pass through. Depending on the shape and size of the aperture, the cross section of the illumination radiation can be shaped and a polygonal light spot 5 in the illumination plane 12 can be achieved. Alternatively, a microlens array can be used for beam homogenization.

[0069] Köhler illumination can also be used if an LED is used as light source 1. In this case, the light source 1 is imaged into the pupil instead of directly into the illumination plane 12.

[0070] Figure 5 A schematic diagram of a third exemplary embodiment of a microscope M with a computer-generated hologram and beam shaping is shown. With the aid of the Gerchberg-Saxton algorithm, for example, a uniform top-hat beam with a hexagonal cross section is generated in the pupil plane with the aid of a spatial light modulator 22. The occurring speckle can be reduced or eliminated, for example, by the measures mentioned further above. The spatial light modulator 22 can be controlled with the aid of control commands from the controller 15.

[0071] If the shaped illumination radiation has a polygonal, in particular hexagonal, cross section, the imaging of the light source 1 can be performed critically or by means of Köhler illumination.

[0072] The scanning of a surface area 11 according to the method according to the invention will be explained below using the example of a hexagonal light spot 5 with a top-hat distribution of its intensity. In order to carry out the method according to the invention, at least one polygonal light spot 5 ( Figure 6 ). The surface area 11 to be illuminated is located therein, which surface area 11 can be, for example, a part of the surface of the sample 10 (see Figures 3 to 5 ).

[0073] As already explained above, multiple light spots 5 are generated simultaneously or with (sequential) time shifts. Due to their polygonal shape, these spots have straight sections of their outer boundaries. These sections (also called illumination boundaries BG) are used to bring the light spots 5 into adjacent arrangements without any space between them and with as little overlap as possible. In this way, complete illumination of the surface area 11 to be illuminated becomes possible. At the same time, the number of required illumination events (light spots 5) can be greatly reduced compared to prior art solutions.

[0074] Figure 7The scanning of the surface area 11 shown therein is schematically shown. The continuously generated light spots 5 are all shown for illustrative purposes and are surrounded by interrupted solid lines. Due to their hexagonal shape, the light spots 5 can be seamlessly connected together at their multiple illumination boundaries. Thus, for example, the surface area 11 can be scanned column by column, wherein the light spots 5 along the respective columns in the column direction are each offset by half the distance of the light spots 5. In this way, the areas illuminated by the respective light spots can be seamlessly meshed with each other. In order to avoid the residual surface area at the edge of the surface area 11 from being illuminated, an additional light spot 5 can be generated, which extends slightly beyond the surface area 11, or its size is selected so that no residual surface area remains or only an acceptable residual surface area remains.

[0075] To illustrate this, three successively generated light spots 5 are highlighted by shading in the right outer column. The three light spots 5 occurring most recently are shown here as slightly dashed lines, while the currently generated light spot 5 is shown with the strongest shading and surrounded by a solid line.

[0076] Reference numerals

[0077] 1 Light Source

[0078] 2 Illumination beam path

[0079] 2T Partial beam path

[0080] 3Optical lens, optical unit

[0081] 4 Microlens Array

[0082] 5. Spot, Spot, Focus

[0083] 6 Coupling optical unit

[0084] 7 Optical fiber

[0085] 8 Beam splitter

[0086] 9 Objective lens

[0087] 10 samples

[0088] 11 Surface Area

[0089] 12 Lighting planes

[0090] 13 Sample stage

[0091] 14. Drive

[0092] 15 Controller

[0093] 16 evaluation units / display

[0094] 17 Detection beam path

[0095] 18 tube lens

[0096] 19 detectors

[0097] 20Diffuser Panel

[0098] 21 aperture

[0099] 22 Light manipulator, SLM

[0100] BG straight section, lighting border

[0101] M microscope

[0102] oA optical axis

Claims

1. A method for illuminating a surface area (11), the surface area (11) being located in an illumination plane (12) and being illuminated with at least one light spot (5) of illumination radiation shaped in the illumination plane (12), The method comprises the following steps: providing illumination radiation along an illumination beam path (2); shaping the illumination radiation and generating the light spot (5) in the illumination plane (12); Features Each affected light spot (5) has a polygonal shape, the outline of which has a plurality of straight segments (BG); wherein the intensity of the shaped illumination radiation is shaped into a top hat distribution by the polygonal shape; as well as The light spots (5) are produced so that respective ones of their straight sections (BG) adjoin each other in the illumination plane (12).

2. The method according to claim 1, characterized in that The surface area (11) to be illuminated is scanned with a plurality of light spots (5) generated and adjoining one another.

3. The method according to claim 1 or 2, characterized in that: The polygonal shape of the light spot (5) is a hexagon, a heptagon, an octagon or a decagon.

4. The method according to any one of the preceding claims, characterized in that The areas of the surface area (11) respectively illuminated by mutually adjacent light spots (5) overlap by at most 10%, preferably at most 5%, of their total surface area.

5. The method according to any one of the preceding claims, characterized in that In each case, a measured value is acquired from the region of the surface region (11) illuminated by the light spot (5) by means of detection radiation which is caused by the illumination radiation, which is acquired as the measured value and is stored as an assignment to the respective light spot (5).

6. The method according to claim 5, characterized in that The stored measured values ​​are combined by using the measured values ​​according to the spatial position of the respective light spot (5) to form an image as individual image data and the stored measured values ​​are arranged adjacent to each other in the correct position and orientation.

7. A device for illuminating a surface area (11), said surface area (11) being located in an illumination plane (12) and being illuminated with at least one spot (5) of illumination radiation shaped in said illumination plane (12), The device comprises a light source (1) for providing the illumination radiation; a beam shaping optical unit (3, 4, 7, 21, 22) arranged in the illumination beam path (2) downstream of the light source (1) for shaping the illumination radiation; a beam deflecting device and / or a holding device (13) with controlled sliding, on which the surface area (11) to be illuminated is held; Features The beam shaping optical unit (3, 4, 7, 21, 22) is designed to generate a light spot (5) having a polygonal shape in the illumination plane (12), wherein the intensity of the shaped illumination radiation is formed in the form of a top-hat distribution over the range of the light spot (5); as well as Using an existing controller (15), light spots (5) are generated, each of which has straight sections (BG) of its contour adjoining each other in the illumination plane (12).

8. The device according to claim 7, characterized in that In order to shape the illumination radiation, at least one beam-limiting optical element (21) is arranged in the illumination beam path (2), which serves to guide only a portion of the illumination radiation to the surface area (11) to be illuminated, where the light spot (5) is generated.

9. The device according to claim 7, characterized in that at least one optical element (4) is arranged in the illumination beam path (2), the at least one optical element (4) being used to split the illumination radiation into a plurality of partial beams (2T), There is at least one optically active element (3, 7, 9) by means of which at least some of the partial beams (2T) are combined and optionally superimposed on one another.

10. The device according to claim 7, characterized in that At least one optical element (3, 22) is present in the illumination beam path (2) for redistributing the light of the illumination radiation within the illumination beam path (2), and at the end of the illumination beam path (2) there is a light spot (5) with a top-hat distribution of the desired polygonal shape and the intensity.

11. The device according to claim 10, characterized in that The optical element is a spatial light modulator (SLM) or a diffractive optical element (DOE).

12. The device according to claim 10 or 11, characterized in that The optical element is a grating.

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