Optical assembly for an oblique plane microscope to improve resolution

Abstract

The invention relates to an optical assembly for an oblique-plane microscope, for example an OPM microscope or a SCAPE microscope. In the prior art, the possible resolution is limited by the numerical aperture (NA) of the imaging optics.SOLUTION: The optical assembly (101) comprises an optical illumination and detection assembly (107) for illuminating the sample volume (117) and for transmitting scattered and / or fluorescent light (129) into a real intermediate image plane (133), an optical erecting unit (139) for imaging onto the detector (143), and an attachment element (145) arranged on the erecting unit (139) and having a boundary surface (147), the beam path (137) of the illumination light (115) and the beam path of the scattered and / or fluorescent light (129) intersect one another on the image side (123), and the beam path (225b) of the illumination light (115) is spaced apart from the boundary surface (147).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an optical assembly for an oblique plane microscope, such as an oblique plane illumination microscope (OPM) or a swept confocal array plane excitation microscope (SCAPE). [Background technology]

[0002] Prior art solutions may also have the drawback of limited resolution due to a limited numerical aperture NA, being sensitive to dust and similar contaminants, or requiring additional optical elements for the introduction of illumination light, which reduces efficiency. Summary of the Invention [Problem to be solved by the invention]

[0003] The present invention seeks to eliminate these drawbacks and provide an optical assembly for an oblique plane microscope that allows not only higher resolution but also higher light throughput. [Means for solving the problem]

[0004] The present invention solves the above-mentioned problems with the optical assembly described at the beginning by having an optical illumination and detection assembly configured to transmit illumination light in the direction of a sample volume, to form a light sheet in the sample volume using the illumination light that is oriented obliquely with respect to the optical axis of the illumination and detection assembly, and to capture and transmit scattered light and / or fluorescent light from an illuminated area of ​​the sample volume illuminated by the light sheet, the optical illumination and detection assembly further configured to image the illuminated area of ​​the sample as a real intermediate image in a real intermediate image plane, the real intermediate image plane being oriented obliquely with respect to the optical axis of the optical illumination and detection assembly and formed on the image side of the illumination and detection assembly opposite the sample volume. The optical assembly further comprises an optical erection unit for imaging the real intermediate image onto the detector, the optical axis of the erection unit being inclined with respect to the optical axis of the optical illumination and detection assembly and oriented substantially perpendicular to the real intermediate image plane, and an attachment element arranged on the erection unit and extending in the direction of the real intermediate image, the attachment element forming a boundary surface oriented substantially parallel to the real intermediate image plane. According to the invention, the optical paths of the incident illumination light and the optical paths of the scattered light and / or fluorescent light transmitted by the illumination and detection assembly intersect each other on the image side of the illumination and detection assembly, and the optical path of the illumination light is spaced apart from the boundary surface of the attachment element.

[0005] Such a separation can be achieved by the optical path of the illumination light and the boundary surface of the attachment element being offset parallel to one another or being inclined relative to one another. Both possibilities will be mentioned later in this specification. This ensures that the optical path of the illumination light does not extend through the boundary surface. The concept of "separated" therefore means that the optical path of the illumination light does not impinge on the boundary surface.

[0006] The optical assembly according to the present invention thus has the advantage that the attachment element can increase the numerical aperture (NA) of the erector unit. The increased numerical aperture has a positive effect on the image resolution of the erector unit, i.e., it increases the resolution. Furthermore, due to the separation between the optical path of the illumination light and the boundary surface of the attachment element, the illumination light can enter the illumination and detection assembly unimpeded on the image side of the illumination and detection assembly opposite the sample volume. This eliminates the need for additional optical elements, such as dichroic mirrors. Dichroic mirrors, which are often used in the prior art, have the disadvantage that they are placed in the optical path of scattered light and / or fluorescent light in conventional optical illumination and detection assemblies, which can weaken and / or limit the scattered light and / or fluorescent light.

[0007] Another advantage of such an assembly according to the invention is the possibility of displacing the light sheet formed in the sample volume and thereby scanning the sample by moving at least one element of the illumination and detection assembly in the direction of the optical axis of the illumination and detection assembly, which is not possible if the incidence is via a dichroic mirror in the illumination and detection assembly. Due to the separation of the optical path of the illumination light from the boundary surface of the attachment element, the assembly according to the invention allows the illumination light to be incident on the illumination and detection assembly unhindered on the image side of the illumination and detection assembly opposite the sample volume.

[0008] The optical assembly can be improved by further additional technical features. Possible configurations with additional technical features are described below. The technical features of the different configurations can be combined with each other in any way and can be omitted if the technical effect associated with the omitted technical feature does not specify the present invention.

[0009] The optical illumination and detection assembly is preferably configured symmetrically or nearly symmetrically. That is, the optical illumination and detection assembly can be configured from the same optical components when viewed from the top side facing the sample volume and from the opposite image side. The illumination and detection assembly is therefore mirror-symmetrical with respect to a plane oriented perpendicular to the optical axis of the illumination and detection assembly and located at the center of the illumination and detection assembly. If different objective lenses are required in the device according to the present invention, the optical illumination and detection assembly is identical to the above description of a nearly symmetrical structure only in terms of the general structural design with respect to the function of the components used: that is, a structure consisting of an objective lens, an imaging lens, possibly two scanning lenses, an imaging lens, and an objective lens. The focal length and / or numerical aperture of each element may be different.

[0010] The illumination and detection assembly may for example be of 4f construction. Preferably, the illumination and detection assembly comprises at least two oppositely oriented objective lenses. Further (imaging) lenses may also be provided.

[0011] Light sheets are known from the prior art, and it is also possible to generate static or quasi-static light sheets (by scanning a line with a light beam). Preferably, in this optical configuration, different areas of the illumination and detection assemblies are used for illumination and for detection, respectively. Thus, the optical paths of the illumination light and the optical paths of the scattered light and / or fluorescent light in the illumination and detection assemblies are spatially separated from each other, but may intersect with each other in the illumination and detection assemblies.

[0012] The advantageously symmetrical structure of the illumination and detection assembly allows a light sheet formed on the image side of the illumination and detection assembly to be imaged into the sample volume. The light sheet imaged into the sample volume illuminates the sample, which emits scattered and / or fluorescent light. This emitted light is collected by the illumination and detection assembly, transmitted towards the image side, and imaged as a real intermediate image in a corresponding intermediate image plane. Both the light sheet to be imaged (imaging from the image side to the sample side) and the illuminated area of ​​the sample volume to be imaged (imaging from the sample side to the image side) are oriented obliquely, i.e., at an angle other than 90°, to the optical axis of the illumination and detection assembly.

[0013] In order to be able to image this obliquely oriented real intermediate image onto the detector without distortion and sharply, the optical axis of the erector unit is tilted with respect to the optical axis of the illumination and detection assembly and is oriented substantially perpendicular to the real intermediate image plane.

[0014] The attachment element can be understood to be an element made of an optical material, preferably having a refractive index higher than that of air. The attachment element may be made of a material that is preferably transparent to at least the wavelengths of scattered light and / or fluorescent light. Preferably, such a material is a glass-like or ceramic-like material, and this material is further preferably transparent to the illumination light. The boundary surface is the boundary surface (side) of the attachment element on the intermediate image side (i.e., the side opposite the erector unit), by which the attachment element is spatially defined. The boundary surface is substantially perpendicular to the optical axis of the erector unit and is typically the end of the attachment element that is spaced away from the erector unit. However, in some configurations, a plane can be defined that at least partially coincides with the boundary surface (i.e., in the region of the boundary surface) and intersects with another region of the attachment element, such as an edge region. These edge regions can further provide fixing structures for fixing the attachment element.

[0015] The attachment element is substantially characterized by its boundary surface. The attachment element can have various shapes, for example, it can be configured as a cube, a cube, or a truncated cone, and the boundary surface is one side of such a structure. If the attachment element is configured as a truncated cone, the bottom surface of such an attachment element is located on the erection unit, and the top surface includes or is the boundary surface. Preferably, the area defined by the boundary surface that can be imaged by the erection unit is larger than the size of the important area of ​​the actual intermediate image, i.e., the area to be imaged (the so-called "region of interest"). Therefore, the boundary surface formed on the attachment element can be at least a part of the boundary surface of the attachment element on the intermediate image side, and this boundary surface is perpendicular to the optical axis of the erection unit.

[0016] The truncated conical configuration of the attachment element has the advantage that it can taper towards the boundary surface, thereby making it possible to position the optical structures relative to each other, i.e., the illumination and detection assembly, the erection unit and, if necessary, the illumination optics, more closely than would be possible with, for example, a cylindrical attachment element.

[0017] According to the invention, both the incidence of the illumination light and the formation of the real intermediate image of the scattered and / or fluorescent light take place on the image side of the illumination and detection assembly, so that the paths of the illumination light and the scattered and / or fluorescent light intersect on this image side. By distancing the paths of the illumination light from the boundary surfaces of the attachment element, shadowing of the illumination light can be avoided and accurate illumination of an area of ​​the sample placed in the sample volume can be ensured.

[0018] The attachment elements may preferably be integrated into the optical erection unit to form one common component, which has the advantage that the common component thus formed can be easily replaced without requiring further orientation or adjustment of the attachment elements relative to the optical erection unit.

[0019] Furthermore, the erection unit can be an immersion objective, which is commercially available and can be used immediately after preparing the corresponding immersion medium. Preferably, however, the attachment element is made of a solid optical material.

[0020] In another configuration of the optical assembly according to the invention, the boundary surface of the attachment element can be arranged at a distance from the actual intermediate image plane in the direction of the optical axis of the erector. Such an arrangement has the advantage that local imperfections at the boundary surface, such as surface roughness, surface inaccuracies, or dust or other foreign matter deposited on the boundary surface, are no longer sharply imaged by the erector on the detector. The influence of such imperfections on the imaging quality of the erector can be significantly reduced by the boundary surface being spaced away from the actual intermediate image plane.

[0021] It is particularly advantageous if the boundary surface has a distance to the actual intermediate image plane that is at least half the maximum light sheet thickness of the illumination light in the direction of the optical axis of the erector. This particularly concerns the region of the light sheet provided on the sample side of the illumination and detection assembly, which is located in front of or behind the boundary surface with respect to the optical axis of the erector. A distance selected in this way has the advantage that the light path of the illumination light does not cross the boundary surface of the attachment element, and can thus reach the illumination and detection assembly unhindered, and the light sheet can be formed in the sample volume after imaging by the illumination and detection assembly.

[0022] The light paths for the illumination light and the scattered and / or fluorescent light can be understood in particular to be specific regions of the light beam within which a predetermined fraction of the observed light beam size of the light beam is measured, where, for example, a Gaussian distribution of the light parameters is measured over the beam cross section, e.g., when the field intensity is 1 / e or when the intensity is 1 / e. 2 When observing in this way, the beam constraint is considered to be the region where the intensity of the beam has dropped to 1.8% of its maximum intensity. Preferably, the diameter of the beam path is such that the intensity (1 / e 2 ) value. In this case, the intensity (1 / e 2 ) value can serve as a lower limit for defining the diameter of the optical path. Preferably, the interval for defining the beam diameter is larger, e.g., (1 / e 2 ) value can be chosen to be five times the intensity (1 / e 2 ) is a drop in the beam's dimensional length, between the point of maximum intensity and the point where the intensity is 1 / e 2 (For a Gaussian ray profile, this length corresponds to the radius.) For non-Gaussian ray profiles, a similar definition to that for the ray diameter can be used.

[0023] The optical assembly can be further improved by the attachment element being cylindrically symmetric with respect to the optical axis of the erector unit. Cylindrical optical materials have the advantage of being easily manufacturable. Using such an attachment element with cylindrical symmetry allows the boundary surface of the attachment element to be positioned away from the actual intermediate image plane in the direction of the optical axis of the erector unit and towards the erector unit. As a result, when viewed from the direction of the erector unit, the optical path of the illumination light passes in front of the attachment element and does not intersect with the boundary surface.

[0024] Alternatively, the attachment element may be arranged at least partially within the optical path of the illumination light. However, this arrangement precludes the use of cylindrically symmetric attachment elements. Therefore, in this arrangement, the boundary surface may be arranged away from the optical erection unit and substantially offset toward the optical illumination and detection assembly. In this arrangement, the optical axis of the illumination optics that provides, i.e., transmits, the illumination light (and thus the optical path of the illumination light) extends through the attachment element.

[0025] This optical axis may preferably be oriented perpendicular to the axis of the erecting unit. In particular, the optical axis of the illumination light may be spaced from the boundary surface by a distance that is at least half the thickness of the light sheet now formed on the attachment element. This configuration ensures that the light sheet, although formed on the attachment element, does not intersect with the boundary surface.

[0026] In this configuration, the attachment element may have an entrance facet configured to allow the illumination light to enter the attachment element and an exit facet configured to allow the illumination light to exit the attachment element. The entrance and exit facets are preferably oriented parallel to each other and more preferably perpendicular to both the optical axis of the illumination optics and the direction of incidence of the illumination light. The use of entrance and / or exit facets arranged at Brewster's angle is also conceivable, but is a very specific configuration of the optical assembly according to the invention.

[0027] As long as the boundary surface is spaced away from the intermediate image plane, further aberrations of the erector unit may occur, which can be suppressed by appropriate measures, for example by using a collimator.

[0028] Alternatively or additionally, the optical assembly according to the present invention may further comprise, in another configuration, a reflective element disposed on the image side of the optical illumination and detection assembly for redirecting illumination light to the optical illumination and detection assembly. The reflective element may be a metallic or dielectric mirror that may be electrically controllable or electrically deformable.

[0029] The reflective element may be located in a region located between the illumination and detection assembly and the erector unit, and preferably the reflective element may be attached to or integrated into the attachment element.

[0030] The use of a reflective element to redirect illumination light to the illumination and detection assembly allows the interface of the attachment element to extend to a real intermediate image plane and allows illumination light to be incident on the image side of the illumination and detection assembly, thereby facilitating scanning of the light sheet within the sample volume by moving at least one element of the illumination and detection assembly along the optical axis of the illumination and detection assembly.

[0031] The use of reflective elements is independent of the position of the boundary surface relative to the intermediate image plane.

[0032] The reflective element may be fixedly attached to the attachment element or may be removably and repeatedly attached to the attachment element. The reflective element may be adjustable on the attachment element or adjusted prior to attachment to the attachment element.

[0033] In another advantageous configuration of the optical assembly according to the invention, the optical assembly further comprises an illumination optics for providing illumination light having an optical axis oriented obliquely relative to the boundary surface. In this configuration, the optical path of the illumination light is oriented obliquely relative to the boundary surface of the attachment element. In another configuration, the optical axis of the illumination optics and the reflecting element for directing the illumination light into the illumination and detection assembly may be oriented such that the reflecting element is oriented parallel to the boundary surface. It is further conceivable that an area of ​​the attachment element adjacent to the boundary surface is mirrored for the illumination light, i.e., reflects the illumination light, so that the reflecting element is formed integrally with the attachment element. Preferably, however, the reflecting element is a separate optical element. In any case, the optical axis of the illumination light is spaced apart from the boundary surface and does not intersect it. In the case of a reflecting area connected to the boundary surface, this reflecting area is not part of the boundary surface of the attachment element.

[0034] Additionally, the illumination optics may be oriented such that its optical axis passes near the attachment element.

[0035] In summary, therefore, there are two possibilities for moving the optical path of the illumination light away from the boundary surface of the attachment element. In one possibility, this is possible by shifting the boundary surface in the direction of the optical axis of the erecting unit. Such a shift can result in the optical path of the illumination light either passing close to the attachment element, i.e. without partially penetrating it, or passing through it.

[0036] Independently of this offset of the boundary surface of the attachment element with respect to the actual intermediate image plane, or independently of the optical path of the illumination light, which by definition is formed as a light sheet in this actual intermediate image plane, it is possible to use a reflecting element for directing the illumination light into the illumination and detection assembly. When using a reflecting element, the distance between the optical path of the illumination light and the boundary surface is not achieved by offsetting the optical path of the illumination light and the boundary surface parallel to each other, but by tilting them relative to each other. Both possibilities can also be combined with each other.

[0037] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items and may be abbreviated as " / ".

[0038] While some aspects have been described in the context of an apparatus, it will be apparent that these aspects also represent a description of a corresponding method, where a block or apparatus corresponds to a step or feature of a step, and similarly, aspects described in the context of a step also represent a description of a corresponding block or item or feature of a corresponding apparatus.

[0039] The optical assembly according to the invention will now be described in detail with reference to the accompanying drawings, which show purely exemplary configurations of the optical assembly according to the invention for oblique plane microscopes or specific exemplary configurations of oblique plane microscopes, and which do not limit the subject matter for which protection is sought, the protection of which is defined by the claims. [Brief explanation of the drawings]

[0040] [Figure 1] 1 shows a first configuration of an optical assembly according to the present invention; [Figure 2] FIG. 2 is a detailed view of a portion of the optical assembly shown in FIG. [Figure 3] FIG. 10 is a detailed view of another configuration of an optical assembly according to the present invention. [Figure 4] FIG. 10 is a detailed view of yet another configuration of an optical assembly according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0041] In the following description, the same technical features and features with the same technical functions are denoted by the same reference numerals. The technical features described below can be combined with each other in any way.

[0042] 1 shows an optical assembly 101 according to the present invention, which may be part of an oblique plane microscope 103, such as an OPM microscope 105. The oblique plane microscope 103 is shown in FIG. 1 only schematically and in outline.

[0043] The optical assembly 101 includes a symmetrically configured optical illumination and detection assembly 107. The optical illumination and detection assembly 107 includes (two) objective lenses 107a and (two) imaging lenses 107b. Due to the symmetrical structure of the optical illumination and detection assembly 107, the optical illumination and detection assembly 107 is a so-called 4f telescope 109.

[0044] The 4f telescope 109 has the property of imaging the light distribution of the illuminated area of ​​the sample, for example, from the first focal plane 111 to the second focal plane 113 with an imaging ratio of 1:1. Since the light path is reversible, it is also possible to image the light distribution from the second focal plane 113 to the first focal plane 111. This is used for illumination.

[0045] The illumination and detection assembly 107 is configured to transmit illumination light 115 towards a sample volume 117 to form a light sheet 121 within the sample volume 117 within which a sample 119 may be located.

[0046] The light sheet 121 can be understood to be a substantially two-dimensional illuminated area, which may be provided statically, for example by the use of a cylindrical lens, or dynamically under the use of pulsed illumination.

[0047] The light sheet 121 shown in the sample volume 117 is already formed on the image side 123 of the optical illumination and detection assembly 107 and is imaged into the sample volume 117 by the illumination and detection assembly 107 .

[0048] In the illustrated configuration, illumination light 115 is incident by illumination optics 125 onto the illumination and detection assembly 107 from image side 123 along optical path 135 of scattered and / or fluorescent light 129. Image side 123 is located on the opposite side of the illumination and detection assembly 107 from the sample volume 117.

[0049] The incidence is preferably on the image side 123, since such incidence makes it possible to move the light sheet 121 within the sample volume 117 by means of a movement 108 of the objective lens 107a, i.e. to scan or scan the sample 119, for example.

[0050] The light sheet 121 is oriented obliquely with respect to the optical axis 127 of the optical illumination and detection assembly 107 both on the image side 123 and within the sample volume 117 .

[0051] An illuminated region 119a of the sample 119 illuminated within the sample volume 117 by the light sheet 121 emits scattered and / or fluorescent light 129, which is simply illustrated by a single symbolic ray.

[0052] The optical illumination and detection assembly 107 collects and transmits the scattered and / or fluorescent light 129. The optical illumination and detection assembly 107 thereby images the illuminated area 119a of the sample 119, illuminated by the light sheet 121, as a real intermediate image 131 in a real intermediate image plane 133 on the image side 123, according to the optical path shown in the figure. The light sheet 121 formed on the image side 123 is also located in this intermediate image plane, so that the optical path 135 of the scattered and / or fluorescent light 129 and the optical path 137 of the illumination light 115 intersect each other on the image side 123.

[0053] The real intermediate image 131 and real intermediate image plane 133 are also oriented obliquely relative to the optical axis 127 of the illumination and detection assembly 107 .

[0054] Furthermore, the optical assembly 101 includes an optical erection unit 139 having an optical axis 141 that is oriented substantially perpendicular to the real intermediate image plane 133 and substantially oblique to the optical axis 127 of the illumination and detection assembly 107. The optical erection unit 139 enables undistorted imaging of the real intermediate image 131 at the detector 143 based on its tilt.

[0055] An attachment element 145 is arranged on the optical erector unit 139 and extends from the erector unit 139 in the direction of the actual intermediate image 131 .

[0056] The attachment element 145 defines a boundary surface 147 that is oriented substantially parallel to the actual intermediate image plane 133. The boundary surface 147 is flat and not curved. Detailed illustrations of the boundary surface 147 are shown in subsequent figures.

[0057] As can be further appreciated in FIG. 1, the optical path 137 of the illumination light 115 is spaced from the boundary surface 147 of the attachment element 145 .

[0058] The attachment element 145 may be integrated into the optical erector unit 139 to form one common component 149 .

[0059] Figures 2 and 3 show enlarged views of one region of the image side 123 of the optical illumination and detection assembly 107. Figure 2 shows the configuration of the optical assembly 101 shown in Figure 1, while Figure 3 shows in detail another configuration of the optical assembly 101 according to the present invention. Other features of the optical assembly 101 not shown in the detailed view remain unchanged.

[0060] Each of these figures shows the light sheet 121, shown hatched, oriented perpendicular to the optical axis 141 of the erector unit 139.

[0061] Both figures show an envelope 251 of the light path 137 of the illumination light 115. This envelope 251 is, for example, a curve that expresses the intensity of the illumination light 115 as a function of the maximum intensity (1 / e 2 ) factor (e is the Euler number, which allows the definition of the cross section of the light beam).

[0062] In both figures, the boundary surface 147 of the corresponding attachment element 145 has a distance D from the real intermediate image plane 133. This distance D is the same for the illustrated configurations of Figures 2 and 3 and, in the illustrated case, is half the light sheet thickness 221a, i.e., in the illustrated example, is 1 / e 2 The interval between the lowering values.

[0063] The optical assemblies 101 according to the present invention in the configurations shown in Figures 2 and 3 differ from each other in terms of the direction along the optical axis 141 of each of the corresponding erector units 139, in which the boundary surface 147 is positioned away from the actual intermediate image plane 133.

[0064] In Figure 2, the boundary surface 147 is receded relative to the intermediate image plane 133 (towards the erection unit 139), whereas in Figure 3 the boundary surface 147 is shifted forward relative to the intermediate image plane 133 (away from the erection unit 139).

[0065] In the configuration shown in FIG. 2, the illumination light 115 does not propagate through the attachment element 145 .

[0066] 3, the optical path 137 of the illumination light 115 is partially within the attachment element 145. To that end, the attachment element 145 has an entrance facet 345a and an exit facet 345b, both of which are oriented parallel to the real intermediate image plane 133 (and thus also to the propagation direction 315a of the illumination light 115) and perpendicular to the optical axis 141 of the erector unit 139.

[0067] 4 shows another configuration of the optical assembly 101 according to the invention. In this configuration, the boundary surface 147 of the attachment element 145 is arranged in the real intermediate image plane 133. With this configuration, it is no longer possible to use the positions of the illumination optics 125 shown in the previous figures, since in this configuration the illumination light 115 would be shadowed at the attachment element 145. Therefore, the illumination position 125a shown in FIGS. 1 to 3 is no longer possible here.

[0068] 4 requires that the illumination optics 125 be positioned at the second illumination position 425b. In the illustrated configuration, the illumination light 115 emitted from the illumination optics 125 is incident on the optical illumination and detection assembly 107 (only the objective lens 107a of the illumination and detection assembly 107 is shown) in the direction of the reflective element 453. The optical axis 157 of the illumination light 115 is then oriented or positioned obliquely, i.e., at an angle 455, relative to the interface 147.

[0069] As can be seen in FIG. 4, in the purely exemplary configuration of FIG. 4 (which differs from the configuration of FIG. 3), the optical axis 157 of the illumination optics 125 is oriented to pass near the attachment element 145 .

[0070] Reflective element 453 is positioned obliquely, or at an angle 455 , relative to interface 147 and is located on image side 123 of optical illumination and detection assembly 107 .

[0071] The reflective element 453 may be permanently attached to the attachment element 145 or may be repeatedly and removably attached.

[0072] The use of the reflective element 453 shown in Figure 4 can be done independently of the deviation of the interface relative to the actual intermediate image plane. Both forms can be combined. [Explanation of symbols]

[0073] 101 Optical Assembly 103 Oblique Plane Microscope 105 OPM microscope 107 Optical illumination and detection assembly 107a Objective Lens 107b Imaging lens 108 Move 109 4f telescope 111 First focal plane 113 Second Focal Plane 115 Illumination 117 Sample volume 119 samples 119a Sample area 121 Light Sheet 123 Image side 125 Illumination optical system 125a First lighting position 127 Optical axis of optical illumination and detection assembly 129 Scattered and / or Fluorescent Light 131 Real intermediate image 133 Real Intermediate Image Plane 135 Path of scattered and / or fluorescent light 137 Light path of illumination light 139 Optical erection unit 141 Optical axis of the erect unit 143 detector 145 Attachment Elements 147 Boundary Surface 149 Common Components 251 Envelope 315a Propagation direction of illumination light 345a entrance facet 345b Exit Facet 425b Second lighting position 453 Reflective Elements 455 angle 157 Optical axis of illumination light D interval

Claims

1. An optical assembly (101) for an oblique plane microscope (103), such as an OPM microscope (105) or a SCAPE microscope, said optical assembly (101) comprising: an optical illumination and detection assembly (107); an optical erection unit (139); an attachment element (145); Equipped with said optical illumination and detection assembly (107) (a) transmitting illumination light (115) toward a sample volume (117) in which the illumination light (115) forms a light sheet (121) that is oriented obliquely with respect to an optical axis (127) of the illumination and detection assembly (107); (b) capturing and transmitting scattered and / or fluorescent light (129) from an illuminated area of ​​the sample volume (117) illuminated by the light sheet (121); It is structured as follows: the optical illumination and detection assembly (107) is configured to image the illuminated region (119 a) of the sample as a real intermediate image (131) in a real intermediate image plane (133), the real intermediate image plane (133) being oriented obliquely with respect to the optical axis (127) of the optical illumination and detection assembly (107) and being formed on an image side (123) of the illumination and detection assembly (107) opposite the sample volume (117); - the optical erection unit (139) for imaging the real intermediate image (131) onto a detector (143), the optical axis (141) of the erection unit (139) being inclined with respect to the optical axis (127) of the optical illumination and detection assembly (107) and oriented substantially perpendicular to the real intermediate image plane (133); - said attachment element (145) is arranged on said erection unit (139) and forms a boundary surface (147) extending in the direction of said real intermediate image (131) and oriented substantially parallel to said real intermediate image plane (133); an optical path (137) of the incident illumination light (115) and an optical path (135) of the scattered light and / or fluorescent light (129) transmitted by the illumination and detection assembly (107) intersect with each other on the image side (123) of the illumination and detection assembly (107), and the optical path (137) of the illumination light (115) is spaced apart from the boundary surface (147) of the attachment element (145); An optical assembly (101).

2. said attachment element (145) being integrated into said optical erection unit (139) to form one common component (149); The optical assembly (101) of claim 1.

3. The erection unit (139) is an immersion objective lens. An optical assembly (101) according to claim 1 or 2.

4. the boundary surface (147) of the attachment element (145) is arranged spaced apart from the actual intermediate image plane (133) in the direction of the optical axis (141) of the erector unit (139); An optical assembly (101) according to any one of claims 1 to 3.

5. the boundary surface (147) has a distance (D) to the actual intermediate image plane (133) that is at least half the maximum light sheet thickness (221 a) of the illumination light (115) in the direction of the optical axis of the erector unit (139); The optical assembly (101) of claim 4.

6. The attachment element (145) is formed cylindrically symmetrically with respect to the optical axis (141) of the erecting unit (139). An optical assembly (101) according to any one of claims 1 to 5.

7. The attachment element (145) is at least partially disposed within the optical path (137) of the illumination light (115). An optical assembly (101) according to any one of claims 1 to 5.

8. the optical assembly (101) further comprises a reflective element (453) disposed on the image side (123) of the optical illumination and detection assembly (107) for redirecting the illumination light (115) into the optical illumination and detection assembly (107); An optical assembly (101) according to any one of claims 1 to 7.

9. The reflective element (453) is attached to or integrated into the attachment element (145); The optical assembly (101) of claim 8.

10. The optical assembly (101) further comprises an illumination optical system (125) for providing the illumination light (115), the illumination optical system (125) having an optical axis (157) oriented obliquely with respect to the boundary surface (147). An optical assembly (101) according to claim 8 or 9.

11. The optical axis (157) of the illumination optical system (125) is directed to pass through the vicinity of the attachment element (145). The optical assembly (101) of claim 10.

12. the attachment element (145) comprises an optical material having a refractive index higher than that of air; An optical assembly (101) according to any one of claims 1 to 11.

13. the attachment element (145) is made of a material that is transparent to at least the wavelength of the scattered light and / or the fluorescent light; An optical assembly (101) according to any one of claims 1 to 12.

14. The optical assembly (101) further comprises a fixing structure for fixing the attachment element (145), the fixing structure being provided on an edge region of the attachment element (145). An optical assembly (101) according to any one of claims 1 to 13.

15. The attachment element (145) is formed in the shape of a cube, a dice or a truncated cone. An optical assembly (101) according to any one of claims 1 to 14.

16. The optical assembly (101) comprises a frustoconical attachment element (145), the bottom surface of which is located on the erecting unit, and the top surface of which includes the boundary surface; The optical assembly (101) of claim 15.

17. The attachment element (145) has an entrance facet configured to allow the illumination light to enter the attachment element (145) and an exit facet configured to allow the illumination light to exit the attachment element (145). An optical assembly (101) according to any one of claims 7 to 16.

18. The reflective element (453) is fixedly or removably attached to the attachment element (145); An optical assembly (101) according to any one of claims 8 to 17.

19. The reflective element (453) is integrally formed with the attachment element (145). An optical assembly (101) according to any one of claims 8 to 18.

Images