Optical apparatus and method for imaging radiation

Abstract

The invention relates to an optical apparatus (1) comprising an objective (2) and an optical inversion device (3) which are arranged along a beam path (4) of radiation (5). According to the invention, the inversion device (3) has a front inversion half (6) and at least one rear inversion half (7) spaced apart from the front inversion half (6) along the beam path (4), wherein an air gap (8) is formed between the front inversion half (6) and the rear inversion half (7), into which air gap a beam-splitter device (9) can be introduced such that the radiation (5) can be at least partially coupled out of the beam path (4) into a side beam path (10).

Description

[0001] Optical device and method for imaging radiation

[0002] This application claims priority from German patent application No. 10 2023 125 049.3, the contents of which are incorporated herein by reference.

[0003] The invention relates to an optical device having an objective lens and an optical reversing device arranged along a beam path of a radiation.

[0004] The invention further relates to a method for imaging radiation using an objective lens and an optical reversing device arranged along a beam path of the radiation.

[0005] Optical devices comprising a lens and an optical reversing device or system are known from the prior art. Such optical devices can also be referred to as reimagers.

[0006] In the optical devices known from the prior art, the lens images an object located at infinity or finite distance onto an intermediate image. In the solutions known from the prior art, this intermediate image is imaged by the reversing device or system onto a focal plane array (FPA) of a detector device.

[0007] From DE 10 2012 005 938 B4, a multispectral zoom lens is known comprising, along a common imaging path, at least one optical zoom group displaceable along the imaging path and a beam splitter element which is configured to split the beam path for a first spectral range along a first optical axis and for a second spectral range along a second optical axis.

[0008] A refractive broadband IR lens is known from DE 44 17 888 A1. In this multi-lens infrared lens with broadband color correction, particularly in the spectral range from 1.4 to 5 pm, silicon is used as the material for lenses with a negative focal length.

[0009] From US 2005 / 0225881 A1 a mirror-based imaging system with two modes is known, which has an objective arrangement with a primary mirror which has a hole in its central region.

[0010] From US 5,781,336 it is known to detect multi-spectral images using a refractive objective lens system.

[0011] US Pat. No. 4,999,005 discloses a refractive lens system for the infrared range, which exhibits color-correcting properties for radiation within a spectral band of 3 to 13 pm. US Pat. No. 4,989,962 discloses a telescope with a dual field of view, which can be used both in the infrared spectral band of 3.8 to 5 pm and in the longer infrared spectral band of 8 to 11.5 pm.

[0012] From US 6,018,414 an infrared lens arrangement is known which can be used in the near-infrared wavelength band and the far-infrared wavelength band to focus infrared radiation onto an image plane.

[0013] From US 7,369,303 B2 an imaging system and a lens system are known which comprise at least one cast chalcogenide lens element.

[0014] From US 7,218,444 B2 an imaging device is known which comprises a refractive imaging device which is arranged in an optical path.

[0015] A disadvantage of the solutions known from the prior art is that when imaging radiation that includes several wavelengths, chromatic aberrations occur, which can make precise imaging difficult.

[0016] The present invention is based on the object of creating an optical device which avoids the disadvantages of the prior art, in particular enabling precise imaging of radiation.

[0017] According to the invention, this object is achieved by an optical device having the features mentioned in claim 1.

[0018] The present invention is further based on the object of creating a method which avoids the disadvantages of the prior art, in particular enabling precise imaging of radiation.

[0019] According to the invention, this object is achieved by a method having the features mentioned in claim 15.

[0020] The optical device according to the invention comprises at least one objective lens and an optical reversing device arranged along a beam path of a radiation. It is provided that the reversing device has a front reversing half and at least one rear reversing half spaced apart from the front reversing half along the beam path, wherein an air gap is formed between the front reversing half and the rear reversing half, into which air gap a beam splitter device can be introduced such that the radiation can be at least partially decoupled from the beam path into a side beam path. In the context of the invention, a reversing half is understood to be an optically effective part of the reversing device. Contrary to the wording, this does not necessarily have to be a half portion.

[0021] By providing the air gap into which the beam splitter device can be inserted to couple out the radiation, the optical device according to the invention enables modular use in systems which provide one or two detectors.

[0022] Thus, the reversing device of the optical device according to the invention is divided into two parts. The air gap, which is preferably relatively large and is referred to below as LIUH2UH, is arranged between the first, front, and the second, rear reversing halves.

[0023] Preferably, in the optical device according to the invention, the reversing device has a defined imaging scale, which is referred to below as ßus.

[0024] It is preferably provided that 0 < | ßus | < 1 , particularly preferred is an embodiment in which 0.5 < | ßus | < 0.9.

[0025] Often, aberrations of the lens in the intermediate image plane are transferred to the image plane of the optical device by the reversing device.

[0026] The image scale represents an important transmission factor of the reversing device.

[0027] The lens's aberrations are also affected by the effect of the magnification. In a case where 0 < | ßus | < 1 , the lens's aberrations are reduced in size in the image plane.

[0028] In a case where 1 < | ßus |, the lens's aberrations in the image plane are magnified. Particularly with regard to the overall correction of the optical image, it is advantageous if the lens's aberrations, which may be unavoidable, are imaged in a reduced size, ie, the magnification of the reversing device is selected such that 0 < | ßus | < 1 .

[0029] In an advantageous development of the optical device according to the invention, it can be provided that the objective and the front reversing half have a plurality of lenses, wherein lenses with positive refractive power or positive lenses or converging lenses are formed partially or entirely from germanium and lenses with negative refractive power or negative lenses or converging lenses are formed partially or entirely from zinc sulfide.

[0030] Preferably, achromatization can be performed using the materials zinc sulfide (ZnS) in the at least one negative lens and germanium (Ge) in the at least one positive lens. This contrasts particularly with known solutions in which a chalcogenide glass is used in the positive lens and ZnS and Ge or other materials are used in the at least one negative lens.

[0031] Alternatively or additionally, the lenses may be formed partially or exclusively from crystalline materials, such as germanium, silicon (Si), zinc sulfide, zinc selenide (ZnSe), barium fluoride (BaF), or gallium arsenide (GaAs). Preferably, it may be provided that exclusively germanium, zinc sulfide, and / or silicon are used.

[0032] In an advantageous development of the optical device according to the invention, it can be provided that a first detector device is provided for detecting the radiation and is arranged in the beam path behind the reversing device.

[0033] If the first detector device is provided as part of the optical device and arranged in the beam path behind the reversing device, an advantageously compact overall system can be formed.

[0034] Preferably, in the optical device according to the invention, both the imaging of an object scene onto an image plane and an imaging of an intermediate plane between the first reversal half and the second reversal half onto the image plane are corrected, preferably chromatically corrected.

[0035] It can be provided that several, in particular two, sections of the optical device are optically corrected.

[0036] It is particularly advantageous if the position of the image plane of the optical system consisting of the lens and the reversing device and the position of the focal plane array or focal plane array of the detector device are spatially congruent. The focal plane array is preferably configured for radiation detection and is particularly designed as a CCD array or a CMOS array.

[0037] If it is advantageously provided that the intermediate image plane is optically, in particular chromatically, corrected, optical markers can be applied in the intermediate image plane, which are sharply imaged by the reversing device onto the first detector device and / or a second detector device, which will be discussed in more detail later.

[0038] In an advantageous development of the optical device according to the invention, at least one diffuser lens can be provided and can be introduced, preferably pivoted, into the air gap in such a way that an image of an object point is defocused by the diffuser lens.

[0039] By incorporating the diffuser lens, an average scene temperature can advantageously be detected. The diffuser lens preferably images an object point with a strong defocus; particularly preferably, a spot diameter or image spot diameter of a light beam on the detector side is larger than a detector surface or FPA surface of the detector device.

[0040] The diameter of an axial bundle with the diffuser lens pivoted in is therefore preferably larger than the detector surface.

[0041] Particularly preferably, the at least one diffuser lens consists of Ge.

[0042] In an advantageous development of the optical device according to the invention, it can be provided that a second rear reversing half is provided and arranged in the side beam path.

[0043] If a second rear reversing half, different from the first, is present, a special adaptation to the optical requirements and conditions prevailing there can be achieved in each of the two beam paths, ie the beam path and the side beam path.

[0044] In an advantageous development of the optical device according to the invention, it can be provided that the beam splitter device has a spectral splitter, which is designed in particular as a splitter plate, and which reflects a first spectral range of the radiation and transmits a second spectral range of the radiation.

[0045] In general, the optical device according to the invention is particularly suitable for imaging radiation from two different spectral ranges. This also applies if the beam splitter device is not incorporated into the optical device.

[0046] To image an object scene, it is necessary that the entire system consisting of lens and reversing device is corrected for both spectral ranges.

[0047] This allows image aberrations of the lens to be compensated by the reversing device and image aberrations of the reversing device can also be compensated by the lens.

[0048] Preferably, the optical system additionally images the intermediate image plane arranged between the reversing halves sharply onto the image plane of the overall system, preferably in the region of the focal plane array of the detector device.

[0049] In this case, however, the aforementioned property of mutual compensation of aberrations can no longer be utilized, or can only be utilized to a very limited extent. It is therefore particularly advantageous if both the intermediate image plane and the image plane are optically corrected, especially chromatically.

[0050] Within the scope of the present invention, the properties explained below in connection with the first and second spectral ranges are also to be understood independently of the respective presence of the beam splitter device in the beam path.

[0051] In particular, the present optical device according to the invention can be understood as a dual-band optical device with respect to two spectral bands.

[0052] In an advantageous development of the optical device according to the invention, it can be provided that the first spectral range, preferably exclusively, comprises an MWIR spectrum, in particular a wavelength range of the radiation from 3 pm to 6 pm, preferably 3.5 pm to 5 pm, and / or the second spectral range, preferably exclusively, comprises an LWIR spectrum, in particular a wavelength range of the radiation from 7 pm to 13 pm, preferably 8 pm to 13 pm.

[0053] Particularly preferably, the beam splitter device is designed as a splitter plate which reflects the first spectral range and transmits the second spectral range, wherein preferably the MWIR spectrum is reflected and the LWIR spectrum is transmitted.

[0054] The spectrum imaged by the lens is both the MWIR spectrum and the LWIR spectrum.

[0055] Preferably, the lens is color corrected in a wavelength range from 3.5 pm to 12 pm.

[0056] Preferably, for a centroid wavelength of the MWIR spectrum, which is given by AS-MWIR, the following applies: AI-MWI < AS-MWIR < A2-MWIR.

[0057] In an analogous manner, the following preferably applies to a centroid wavelength of the LWIR spectrum, which is given by AS-LWIR: AI-LWIR < AS-LWIR < A2-LWIR.

[0058] AI-LWIR, A2-LWIR, AI-MWIR and A2-MWIR give the respective upper and lower edge wavelengths of the respective partial spectra.

[0059] Preferably, the respective centroid wavelengths can be arranged centrally in the partial spectra. The focal length of the lens for the centroid wavelength of the MWIR spectrum in the intermediate image plane is referred to below as s S-MWIR. Similarly, the focal length of the lens for the centroid wavelength of the LWIR spectrum in the intermediate image plane is referred to as S' S-LWI.

[0060] A difference in an image position in the intermediate image plane for the respective centroid wavelengths can be determined as the back focal length difference As'. Here, As' = | S'S-MWI - S'S-LWIR|.

[0061] Preferably, the focal length difference As' of the lens can be set to: As' < 0.1, preferably As' < 0.05. The stated values ​​are preferably in millimeters.

[0062] In an advantageous development of the optical device according to the invention, it can be provided that a first operating mode is provided, wherein in the first operating mode only the air gap is arranged between the front reversing half and the rear reversing half.

[0063] If only the air gap is arranged between the two reversing halves, the optical device according to the invention can also be operated with only one detector device, namely the first detector device. This provides increased flexibility with regard to modular use with one or two detectors.

[0064] In an advantageous development of the optical device according to the invention, it can be provided that in the first operating mode the rear reversing half has, preferably exclusively, two lenses, in which a diverging lens is arranged in front of a converging lens in a propagation direction of the radiation.

[0065] If the second reversing half in the first operating mode consists of two lenses with the refractive power arrangement “diverging lens and converging lens”, the following three embodiments advantageously result:

[0066] In a first embodiment, in the rear reversing half, the diverging lens or the lens with negative refractive power preferably consists partly or completely of ZnS and the converging lens or the lens with positive refractive power consists partly or completely of Ge.

[0067] In a second embodiment, in the rear reversing half, the diverging lens or the lens with negative refractive power preferably consists partly or completely of BaF and the converging lens or the lens with positive refractive power consists partly or completely of Ge.

[0068] In a third embodiment, the diverging lens or the lens with negative refractive power consists partially or entirely of ZnS, and the converging lens or the lens with positive refractive power consists partially or entirely of GaAs. In an advantageous development of the optical device according to the invention, a second operating mode can be provided, wherein in the second operating mode, the beam splitter device is present as part of the optical device and is arranged such that the radiation is at least partially decoupled from the beam path into the side beam path, and a second detector device for detecting the decoupled radiation is present and arranged in the side beam path.

[0069] The optical device according to the invention can therefore be operated in two modes.

[0070] In the first operating mode, which can also be referred to as a “dual-band reimager with one detector”, a single detector device follows the rear reversing half, which is light-sensitive in both the MWIR spectrum and the LWIR spectrum.

[0071] In the second operating mode, which can also be referred to as a “dual-band reimager with two detectors”, the front reversing half is followed by the beam splitter device, which is preferably designed as a spectral splitter.

[0072] In particular, it can be provided that the beam splitter device divides the total spectral range of the radiation into the first spectral range, ie the MWIR spectrum, and the second spectral range, ie the LWIR spectrum.

[0073] Particularly preferred is an embodiment in which the first spectral range is imaged onto the first detector device and the first detector device is configured, in particular optimized, to detect radiation of the first spectral range, in particular the MWIR spectrum.

[0074] Furthermore, an embodiment is advantageous in which the radiation of the second spectral range is imaged onto the second detector device, wherein the second detector device is configured, in particular optimized, for detecting the second spectral range, in particular the LWIR spectrum.

[0075] Of particular advantage is an embodiment in which aperture numbers, which can be referred to as f / #, and a position of a cold aperture in the first detector device, in particular the MWIR detector, and the second detector device, in particular the LWIR detector, are different from one another.

[0076] In an advantageous development of the optical device according to the invention, the beam splitter device can be provided with a ZnS material, preferably made of ZnS. Within the scope of the invention, the use of zinc sulfide or ZnS to form the beam splitter device for separating the first and second spectral ranges has proven particularly advantageous.

[0077] In an advantageous development of the optical device according to the invention, it can be provided that in the second operating mode, the rear reversing half and / or the second rear reversing half is each formed from a lens with positive refractive power, which is adapted to the respective spectral range.

[0078] The respective rear reversing halves preferably consist of one lens each in each spectral path, ie preferably the MWIR path and the LWIR path.

[0079] Preferably, the single lens in the MWIR path is made of silicon and / or has a positive refractive power. The focal length of this lens is preferably designated F2U-MWIR.

[0080] Preferably, the single lens of the second rear reversing half in the LWIR path is made of germanium and / or has a positive refractive power. The focal length of this lens is preferably referred to as F2U-LWIR.

[0081] The difference between the focal lengths described above is referred to below as AF211 in the respective rear half of the lens.

[0082] The difference AF211 is preferably calculated using formula (1). ioo[%] (1)

[0083] Particularly preferred is an embodiment in which AF211 < 5 [%].

[0084] In an advantageous development of the optical device according to the invention, it can be provided that the beam splitter device is arranged tilted to the beam path at an angle of 40° to 50°, preferably 44.5° to 45.5°.

[0085] Preferably, the air gap LIUH2UH is at least large enough that a beam splitter device inclined by 45°, which is preferably designed as a splitter plate, can be integrated into the optical device.

[0086] The aforementioned minimum distance LIUH2UH is preferably calculated from a diameter of the front reversing half, which is referred to below as DIUH, and a diameter of the rear reversing half, which is referred to below as D211H, according to the formula (2).

[0087] In both operating modes, the lens preferably consists partially or completely of three lenses arranged along the optical axis in the direction of the radiation with the following refractive power arrangement: lens with positive refractive power (converging lens), lens with negative refractive power (diverging lens) and lens with positive refractive power (converging lens).

[0088] Likewise, it is preferably provided that in both operating modes the front reversing half preferably consists partially or completely of two lenses with the following refractive power arrangement: lens with negative refractive power (diverging lens) and lens with positive refractive power (converging lens).

[0089] In a particularly preferred embodiment, the design data of the lenses used in the objective and the front reversing half are identical in both operating modes. The design data of the lenses include, in particular, parameters such as a radius, a thickness, a material, and / or data regarding the asphericity of the respective lens.

[0090] Advantageously, it can be provided that in the optical device according to the invention, a diffuser lens is used in each of the side beam path, ie, in the LWIR path, and the beam path, ie, the MWIR path. Alternatively, it can be provided that only one diffuser lens is used either in the side beam path or in the beam path.

[0091] It can be provided that the diffuser lens is arranged after the front reversing half and in front of the beam splitter device.

[0092] Preferably, a diameter of an axis bundle in a pivoted-in position of the diffuser lens, which is preferably arranged to be pivotable in and out, is larger than a surface of the respective detector device.

[0093] Furthermore, it is preferably provided that the surfaces of the lenses used in both operating modes are designed as spherical and / or aspherical surfaces.

[0094] An aspherical surface of a respective lens or optical element is described by the so-called sagittal formula according to formula (3):

[0095] In formula (3), z indicates a sagittal height, K an eccentricity, p a vertex curvature, h a height, and A, B, C, D respective coefficients for higher-order thermals. In an advantageous development of the optical device according to the invention, it can be provided that at least one image aberration caused by the tilting of the beam splitter device is partially or exclusively compensated by decentering a first group consisting of the rear reversing half and the first detector device and / or by decentering a second group consisting of the second rear reversing half and the second detector device.

[0096] The beam splitter device, which is preferably designed as a splitter plate, is, as described above, preferably tilted by 45° to the optical axis of the beam path.

[0097] Particularly preferred is also an embodiment in which the image errors caused by the tilting of the beam splitter device are preferably compensated exclusively by decentering an optical group consisting of the respective second rear reversing half and the respective detector device.

[0098] The invention further relates to a method having the features mentioned in claim 15.

[0099] The method according to the invention serves to image radiation using an objective lens and an optical reversing device arranged along a beam path of the radiation. In a first operating mode, the radiation is imaged onto a first detector device after the reversing device, and in a second operating mode, a beam splitter device is inserted between a front reversing half and a rear reversing half of the reversing device in such a way that the radiation is at least partially decoupled from the beam path into a side beam path.

[0100] The method according to the invention has the advantage that two operating modes of the method can be realized, particularly by exchanging optical groups or omitting at least one optical group. In particular, an optical device, in particular a so-called dual-band reimager with two detector devices, can be converted with little effort into a dual-band reimager with only one detector.

[0101] Particularly preferably, the optical device according to the invention and / or the method according to the invention can be used for use in a weapon, in particular in the sighting of a weapon.

[0102] Features described in connection with one of the subject matters of the invention, specifically the optical device and the method according to the invention, can also be advantageously implemented for the other subject matters of the invention. Likewise, advantages mentioned in connection with one of the subject matters of the invention can also be understood to apply to the other subject matters of the invention.

[0103] It should also be noted that terms such as "comprising," "having," or "with" do not exclude other features or steps. Furthermore, terms such as "a" or "the," which indicate a singular number of steps or features, do not exclude a plurality of features or steps—and vice versa.

[0104] In a purist embodiment of the invention, however, it may also be provided that the features introduced in the invention with the terms "comprising," "having," or "with" are listed exhaustively. Accordingly, one or more lists of features may be considered complete within the scope of the invention, for example, for each claim. The invention may, for example, consist exclusively of the features mentioned in claim 1.

[0105] It should be noted that terms such as "first" or "second" etc. are used primarily for reasons of distinguishing between respective device or process features and are not necessarily intended to indicate that features are mutually dependent or related to one another.

[0106] In the following, embodiments of the invention are described in more detail with reference to the drawing.

[0107] The figures each show preferred embodiments in which individual features of the present invention are illustrated in combination with one another. Features of one embodiment can also be implemented independently of the other features of the same embodiment and can therefore be readily combined by a person skilled in the art with features of other embodiments to form further useful combinations and subcombinations.

[0108] In the figures, functionally identical elements are provided with the same reference numerals.

[0109] They show:

[0110] Figure 1 is a schematic representation of a possible embodiment of the inventive

[0111] optical device;

[0112] Figure 2 is a schematic representation of another possible embodiment of the optical device according to the invention;

[0113] Figure 3 is a schematic representation of another possible embodiment of the optical device according to the invention; Figure 4 is a schematic representation of another possible embodiment of the optical device according to the invention; and

[0114] Figure 5 is a block diagram representation of a possible embodiment of the method according to the invention.

[0115] Figure 1 shows a schematic representation of a possible embodiment of an optical device 1 with an objective 2 and an optical reversing device 3. The objective 2 and the reversing device 3 are arranged along a beam path 4 of a radiation 5. The reversing device 3 has a front reversing half 6 and at least one rear reversing half 7 spaced apart from the front reversing half 6 along the beam path 4. An air gap 8 is formed between the front reversing half 6 and the rear reversing half 7, into which air gap a beam splitter device 9 (see Figure 2) can be introduced such that the radiation 5 can be at least partially coupled out of the beam path 4 into a side beam path 10 (see Figure 2).

[0116] In the embodiment of the optical device 1 shown in Figure 1, a first detector device 11 for detecting the radiation 5 is preferably present and arranged in the beam path 4 behind the reversing device 3.

[0117] In the embodiment of the optical device 1 shown in Figure 1, a first operating mode is provided for the operation of the optical device 1, wherein in the first operating mode only the air gap 8 is arranged between the front reversing half 6 and the rear reversing half 7.

[0118] Furthermore, in the embodiment of the optical device 1 shown in Figure 1, in the first operating mode, the rear reversing half 6 preferably has two lenses 12, particularly preferably exclusively two lenses 12. In this case, a diverging lens 12a is arranged in front of a converging lens 12b in a propagation direction (indicated by an arrow 13) of the radiation 5.

[0119] Figure 2 shows a schematic representation of another possible embodiment of the optical device 1.

[0120] In the embodiment shown in Figure 2, the beam splitter device 9 is introduced into the air gap 8 in such a way that the radiation 5 is at least partially coupled out of the beam path 4 into the side beam path 10.

[0121] In the embodiment of the optical device 1 shown in Figure 2, a second rear reversing half 14 is preferably present and arranged in the side beam path 10. Furthermore, in the embodiment shown in Figure 2, the beam splitter device 9 has a spectral splitter, which is designed in particular as a splitter plate and which reflects a first spectral range of the radiation 5 and transmits a second spectral range of the radiation 5.

[0122] In the embodiment of the optical device 1 shown in Figure 2, the first spectral range comprises, preferably exclusively, an MWIR spectrum, in particular a wavelength range of the radiation 5 from 3 pm to 6 pm, preferably 3.5 pm to 5 pm.

[0123] Alternatively or additionally, the second spectral range comprises, preferably exclusively, an LWIR spectrum, in particular a wavelength range of the radiation 5 from 7 pm to 13 pm, preferably 8 pm to 13 pm.

[0124] In the embodiment shown in Figure 1, the first detector device 11 is preferably configured to detect both radiation 5 of the first spectral range and radiation 5 of the second spectral range.

[0125] In the embodiment of the optical device 1 shown in Figure 2, a second operating mode is also provided. In the second operating mode, the beam splitter device 9 is present as part of the optical device 1 and is arranged such that the radiation 5 is at least partially coupled out of the beam path 4 into the side beam path 10. Furthermore, a second detector device 15 for detecting the coupled-out radiation 5 is present and arranged in the side beam path 10.

[0126] In the embodiment of the optical device 1 shown in Figure 2, the beam splitter device 9 preferably comprises a zinc sulfide or ZnS. Particularly preferably, the beam splitter device 9 is formed from zinc sulfide.

[0127] In the embodiment of the optical device 1 shown in Figure 2, in the second operating mode, the rear reversing half 7 and / or the second rear reversing half 14 are each formed from a lens 12 with positive refractive power, ie, preferably a converging lens 12b. The lens 12 is adapted to the respective spectral range.

[0128] Furthermore, in the embodiment of the optical device 1 shown in Figure 2, the beam splitter device 9 is arranged tilted to the beam path 4 at an angle of 40° to 50°, preferably 44.5° to 45.5°.

[0129] In the embodiments of the optical device 1 shown in Figures 1 and 2, the objective lens 2 and the front reversing half 6 also have a plurality of lenses 12, wherein the lenses 12b with positive refractive power are preferably formed partially or entirely from germanium, and the lenses 12a with negative refractive power are formed partially or entirely from zinc sulfide. Furthermore, in the embodiments of the optical device 1 shown in Figures 1 and 2, the objective lens 2 consists of three lenses 12, with a refractive power arrangement along the propagation direction 13 defined by: converging lens 12b, diverging lens 12a, and converging lens 12b.

[0130] In the embodiments of the optical device 1 shown in Figures 1 and 2, the front reversing half 6 preferably consists of two lenses 12 with a refractive power arrangement along the propagation direction 13 as follows: diverging lens 12a and converging lens 12b.

[0131] Figures 1 and 2 each also show an intermediate image 16, symbolized by an arrow. Through the action of the reversing device 3, the intermediate image 16 is transformed into image 17 and thereby reversed. This is symbolized in Figures 1 and 2 by an arrow that is reversed compared to the intermediate image 16.

[0132] In the embodiment illustrated in Figure 2, the first detector device 11 is configured or optimized for detecting radiation 5 in the second, i.e., longer-wavelength spectral range. In particular, the detector device 11 is optimized for detecting radiation 5 in the LWIR range.

[0133] Furthermore, in the embodiment shown in Figure 2, the second detector device 15 is preferably optimized for detecting the radiation 5 in the first, ie shorter-wave, spectral range, in particular the MWIR range.

[0134] In the embodiments shown in Figures 1 and 2, the first detector device 11 and / or the second detector device 15 each have a detector window 19 and a cold aperture 20.

[0135] In the embodiments shown in Figures 1 and 2, the image 17 is further arranged or imaged in a plane of a focal plane array (not shown in detail) of the respective detector device 11 or 13.

[0136] In Figures 1 and 2, the image 17 is preferably located on the focal plane array of the respective detector device 11, 15.

[0137] Figure 3 shows a schematic representation of another possible embodiment of the optical device 1.

[0138] The optical device 1 according to the exemplary embodiment shown in Figure 3 is designed analogously to the embodiment shown in Figure 1. Therefore, reference is made at this point to the key to the reference symbols in Figure 1. However, in the optical device 1 according to the exemplary embodiment shown in Figure 3, at least one diffuser lens 18 is preferably additionally present and can be introduced into the air gap 8 in such a way, or in the exemplary embodiment shown in Figure 3, is introduced in such a way that an image of an object point is defocused by the diffuser lens 18.

[0139] In the embodiment shown in Figure 3, the beam path of a parallel input beam of the radiation 5 is shown with a dashed line, wherein the radiation 5 is divergent or defocused in the plane of the focal plane array of the detector devices 11, 15.

[0140] According to the embodiment shown in Figure 3, the diffuser lens 18 is preferably designed to be pivotable.

[0141] Figure 4 shows a schematic representation of another possible embodiment of the optical device 1 according to the invention.

[0142] The embodiment of the optical device 1 shown in Figure 4 represents the optical device 1 in the second operating mode, analogous to the embodiment of the optical device 1 shown in Figure 2.

[0143] However, analogous to the embodiment of the optical device 1 shown in Figure 3, the diffuser lens 18 can be or is introduced after the front reversing half 6 into the beam path 4 in front of the beam splitter device 9 in such a way that the incoming parallel beam bundle is imaged defocused on the respective focus plane arrays of the first detector device 11 and the second detector device 15.

[0144] In the exemplary embodiments illustrated in Figures 2 and 4, in which the beam splitter device 9 is arranged in the beam path 4, it is preferably provided that at least one image error caused by the tilting of the beam splitter device 9 is partially or exclusively compensated by decentering a first group consisting of the rear reversing half 7 and the first detector device 11. Alternatively or additionally, it is preferably provided that at least one image error caused by the tilting of the beam splitter device 9 is partially or exclusively compensated by decentering a second group consisting of the second rear reversing half 14 and the second detector device 15.

[0145] Figure 5 shows a block diagram of a possible embodiment of a method for imaging the radiation 5. In the method for imaging the radiation 5, the objective 2 and the optical reversing device 3, which are arranged along the beam path 4 of the radiation 5, are used.

[0146] In a first operating mode block 30, the radiation 5 is switched to the first

[0147] Detector device 11 is imaged. In a second operating mode block 31, the beam splitter device 9 is inserted in a beam splitting block 32 between the front reversing half 6 and the rear reversing half 7 of the reversing device 3 such that the radiation 5 is at least partially decoupled from the beam path 4 into the side beam path 10 in a decoupling block 33 and preferably imaged onto the second detector device 15.

[0148] Tables 1 to 7 indicate possible embodiments of the optical device 1. The specified parameters A, B, C, and D refer to the asphericity (ASP) given by formula (3). The specified data refer to the surfaces of the optical elements 4 traversed by the radiation 5 in the order of the propagation direction 13 of the radiation 5. Thus, Fl. No. indicates the number of the relevant surface. The values ​​of radius and thickness are preferably given in millimeters. However, the values ​​of radius and thickness can be scaled as desired while maintaining the respective ratios.

[0149] "INFINITY" also describes an infinite radius. The radius "INFINITY" is also commonly used for a non-optically effective surface, and within the scope of the invention. This can occur if the surface in question is not provided for in the respective configuration.

[0150] A refraction-free transition does not necessarily exist in this context, since the radius of a plane plate is infinite, meaning the surface is flat. Nevertheless, refraction does occur in this case (see, for example, points 21 and 22 in Table 1).

[0151] The surfaces designated in Table 1 with the numbers 12-15 have a refraction-free transition, as these are “dummy surfaces” which can be used to indicate, for example, mechanical limitations.

[0152] A possible embodiment of the configuration of the optical device 1 shown in Figure 1 is given by Table 1.

[0153] In the rear reversing half 7, the lens 12 of negative refractive power preferably consists of ZnS (Fl. Nos. 16-17) and the lens 12 of positive refractive power of Ge (Fl. Nos. 18-19).

[0154] Table 1 :

[0155] ASP aspherical surface

[0156] Fl. No. 1 - 6 Lens 2

[0157] Fl. No. 7 Intermediate image 16

[0158] Fl. No. 8 - 11 front half 6

[0159] Fl. No. 12 - 13 diffuser lens 18

[0160] Fl. No. 16 - 19 rear half of turnaround 7

[0161] Panel No. 21 - 22 Detector window 19 Panel No. 23 Cold aperture 20

[0162] Fl. No. 24 Image 17 or FPA (Focal Plane Array)

[0163] Fl. No. Radius Thickness Material

[0164] 1 : 63.02937 4.00 Ge

[0165] 2: -63.13928 2.57

[0166] ASP: A :0.189030E-04 B :-.455008E-07 C :0.111301 E-09 D :-.147047E-12

[0167] 3: 28.97969 2.50 ZnS

[0168] 4: 11.47970 4.02

[0169] 5: 52.43516 3.00 Ge

[0170] ASP: A :-.433845E-06 B :-.412433E-07 C :-.202375E-08 D :0.299389E-10

[0171] 6: 67.48971 3.85

[0172] 7: INFINITY 8.85

[0173] 8: -23.53583 2.50 ZnS

[0174] 9: -127.83322 2.40

[0175] 10: -37.68016 4.00 Ge

[0176] 11 : -22.77495 2.50

[0177] ASP: A :0.168089E-05 B :-.131893E-07 C :0.740219E-10 D :-.194065E-12

[0178] 12: INFINITY 3.00

[0179] 13: INFINITY 1.00

[0180] 14: INFINITY 15.00

[0181] 15: INFINITY 16.40

[0182] 16: 82.05496 2.00 ZnS

[0183] 17: 48.03506 0.26

[0184] 18: 50.98334 3.00 Ge

[0185] ASP: A :-.4128O1 E-05 B :0.149001 E-07 C :-.177196E-09 D :0.106484E-11

[0186] 19: -1556.01445 0.50

[0187] 20: INFINITY 2.50

[0188] 21 : INFINITY 1.00 Ge

[0189] 22: INFINITY 1.57

[0190] 23: INFINITY 20.00

[0191] 24: INFINITY 0.00

[0192] A possible embodiment of the configuration of the optical device 1 shown in Figure 2 in the side beam path 10 or the MWIR path is given by Table 2.

[0193] Table 2:

[0194] ASP aspherical surface

[0195] Bottle No. 1 - 6 Lens 2 Bottle No. 7 Intermediate image 16

[0196] Fl. No. 8 - 11 front half 6

[0197] Fl. No. 12 - 13 diffuser lens 18

[0198] Fl. No. 15 Front surface of the beam splitter device 9

[0199] Fl. No. 17 - 18 rear half of turnaround 7

[0200] Fl. No. 19 - 20 detector window 19

[0201] Bottle No. 21 cold blend 20

[0202] Fl. No. 22 Image 17 or FPA (Focal Plane Array

[0203] Fl. No. Radius Thickness Material

[0204] 1 : 63.02937 4.00 Ge

[0205] 2: -63.13928 2.57

[0206] ASP: A: 0.189030E-04 B: -.455008E-07 C: 0.111301 E-09 D: -.147047E-12

[0207] 3: 28.97969 2.50 ZnS

[0208] 4: 11.47970 4.02

[0209] 5: 52.43516 3.00 Ge

[0210] ASP: A: -.433845E-06 B: -.412433E-07 C: -.202375E-08 D: 0.299389E-10

[0211] 6: 67.48971 3.85

[0212] 7: INFINITY 8.85

[0213] 8: -23.53583 2.50 ZnS

[0214] 9: -127.83322 2.40

[0215] 10: -37.68016 4.00 Ge

[0216] 11 : -22.77495 2.50

[0217] ASP: A: 0.168089E-05 B: -.131893E-07 C: 0.740219E-10 D: -.194065E-12

[0218] 12: INFINITY 3.00

[0219] 13: INFINITY 1.00

[0220] 14: INFINITY 15.00

[0221] 15: INFINITY 15.50

[0222] 16: INFINITY 2.50

[0223] 17: 60.31137 3.50 Si

[0224] ASP: A: -.588522E-05 B: 0.231773E-07 C: -.181798E-09 D: 0.629241 E-12

[0225] 18: -253.39544 7.50

[0226] 19: INFINITY 1.00 Ge

[0227] 20: INFINITY 1.56

[0228] 21 : INFINITY 16.00

[0229] 22: INFINITY 0.00

[0230] A possible embodiment of the configuration of the optical device 1 shown in Figure 2 in the beam path 4 or the LWIR path is given in Table 3. Table 3:

[0231] ASP aspherical surface

[0232] Fl. No. 1 - 6 Lens 2

[0233] Fl. No. 7 Intermediate image 16

[0234] Fl. No. 8 - 11 front half 6

[0235] Fl. No. 12 - 13 diffuser lens 18

[0236] Fl. No. 15 - 16 Beam splitter device 9

[0237] Fl. No. 18 - 19 rear half of turnaround 7

[0238] Fl. No. 19 - 20 detector window 19

[0239] Fl. Nr. 22 Kaltblende 20

[0240] Fl. Nr. 23 Bild 17 bzw. FPA (Focal-Plane-Array

[0241] Fl. Nr. Radius Dicke Material

[0242] 1 : 63.02937 4.00 Ge

[0243] 2: -63.13928 2.57

[0244] ASP: A: 0.189030E-04 B: -.455008E-07 C: 0.111301 E-09 D: -.147047E-12

[0245] 3: 28.97969 2.50 ZnS

[0246] 4: 11.47970 4.02

[0247] 5: 52.43516 3.00 Ge

[0248] 6: 67.48971 3.85

[0249] 7: INFINITY 8.85

[0250] 8: -23.53583 2.50 ZnS

[0251] 9: -127.83322 2.40

[0252] 10: -37.68016 4.00 Ge

[0253] 11 : -22.77495 2.50

[0254] ASP: A: 0.168089E-05 B: -. 31893E-07 C: 0.740219E-10 D: -.194065E-12

[0255] 12: INFINITY 3.00

[0256] 13: INFINITY 1.00

[0257] 14: INFINITY 15.00

[0258] 15: INFINITY 2.00 ZnS

[0259] 16: INFINITY 13.50

[0260] 17: INFINITY 2.50

[0261] 18: 66.53256 4.00 Ge

[0262] ASP: A: -.354005E-05 B: -.103863E-07 C: 0.218672E-09: -.116338E-11

[0263] 19: -595.31453 3.00

[0264] 20: INFINITY 1.00

[0265] 21 : INFINITY 1.57

[0266] 22: INFINITY 20.00 23: INFINITY 0.00

[0267] A possible embodiment of the configuration of the optical device 1 shown in Figure 3 is given by Table 4.

[0268] In the rear reversing half 7, the lens 12 of negative refractive power preferably consists of ZnS (Fl. Nos. 16-17) and the lens 12 of positive refractive power of Ge (Fl. Nos. 18-19).

[0269] Table 4:

[0270] ASP aspherical surface

[0271] Fl. No. 1 - 6 Lens 2

[0272] Fl. No. 7 Intermediate image 16

[0273] Fl. No. 8 - 11 front half 6

[0274] Fl. No. 12 - 13 diffuser lens 18

[0275] Fl. No. 16 - 19 rear half of turnaround 7

[0276] Fl. No. 21 - 22 detector window 19

[0277] Bottle No. 23 cold blend 20

[0278] Fl. No. 24 Image 17 or FPA (Focal Plane Array

[0279] Fl. No. Radius Thickness Material

[0280] 1 : 63.02937 4.00 Ge

[0281] 2: -63.13928 2.57

[0282] ASP: A :0.189030E-04 B :-.455008E-07 C :0.111301 E-09 D :-.147047E-12

[0283] 3: 28.97969 2.50 ZnS

[0284] 4: 11.47970 4.02

[0285] 5: 52.43516 3.00 Ge

[0286] ASP: A :-.433845E-06 B :-.412433E-07 C :-.202375E-08 D :0.299389E-10

[0287] 6: 67.48971 3.85

[0288] 7: INFINITY 8.85

[0289] 8: -23.53583 2.50 ZnS

[0290] 9: -127.83322 2.40

[0291] 10: -37.68016 4.00 Ge

[0292] 11 : -22.77495 2.50

[0293] ASP: A :0.168089E-05 B :-.131893E-07 C :0.740219E-10 D :-.194065E-12

[0294] 12: INFINITY 3.00 Ge

[0295] 13: -62.5000 1.00

[0296] 14: INFINITY 15.00

[0297] 15: INFINITY 16.40

[0298] 16: 82.05496 2.00 ZnS 17: 48.03506 0.26

[0299] 18: 50.98334 3.00 Ge

[0300] ASP: A :-.4128O1 E-05 B :0.149001 E-07 C :-.177196E-09 D :0.106484E-11

[0301] 19: -1556.01445 0.50

[0302] 20: INFINITY 2.50

[0303] 21 : INFINITY 1 .00 Ge

[0304] 22: INFINITY 1 .57

[0305] 23: INFINITY 20.00

[0306] 24: INFINITY 0.00

[0307] Another possible embodiment of the configuration of the optical device 1 shown in Figure 3 is given by Table 5.

[0308] In the rear reversing half 7, the lens 12 of negative refractive power preferably consists of BaF (Fl. Nos. 16-17) and the lens 12 of positive refractive power of Ge (Fl. Nos. 18-19).

[0309] Table 5:

[0310] ASP aspherical surface

[0311] Fl. No. 1 - 6 Lens 2

[0312] Fl. No. 7 Intermediate image 16

[0313] Fl. No. 8 - 11 front half 6

[0314] Fl. No. 12 - 13 diffuser lens 18

[0315] Fl. No. 16 - 19 rear half of turnaround 7

[0316] Fl. No. 21 - 22 detector window 19

[0317] Bottle No. 23 cold blend 20

[0318] Fl. No. 24 Image 17 or FPA (Focal Plane Array)

[0319] Fl. No. Radius Thickness Material

[0320] 1 : 63.02937 4.00 Ge

[0321] 2: -63.13928 2.57

[0322] ASP: A :0.189030E-04 B :-.455008E-07 C :0.111301 E-09 D :-.147047E-12

[0323] 3: 28.97969 2.50 ZnS

[0324] 4: 11.47970 4.02

[0325] 5: 52.43516 3.00 Ge

[0326] ASP: A :-.433845E-06 B :-.412433E-07 C :-.202375E-08 D :0.299389E-10

[0327] 6: 67.48971 3.85

[0328] 7: INFINITY 8.85

[0329] 8: -23.53583 2.50 ZnS

[0330] 9: -127.83322 2.40 10: -37.68016 4.00 Ge

[0331] 11 : -22.77495 2.50

[0332] ASP: A :0.168089E-05 B :-.131893E-07 C :0.740219E-10 D :-.194065E-12

[0333] 12: INFINITY 3.00

[0334] 13: INFINITY 1 .00

[0335] 14: INFINITY 15.00

[0336] 15: INFINITY 15.64

[0337] 16: 54.92564 2.00 BaF

[0338] 17: 39.08474 0.50

[0339] 18: 57.00945 3.00 Ge

[0340] ASP: A :-.378053E-05 B :0.890337E-08 C :-.973818E-10 D :0.694081 E-12

[0341] 19: -3784.63736 0.50

[0342] 20: INFINITY 2.50

[0343] 21 : INFINITY 1 .00 Ge

[0344] 22: INFINITY 1 .57

[0345] 23: INFINITY 20.00

[0346] 24: INFINITY 0.00

[0347] Another possible embodiment of the configuration of the optical device 1 shown in Figure 3 is given by Table 6.

[0348] In the rear reversing half 7, the lens 12 of negative refractive power preferably consists of ZnS (Fl. Nos. 16-17) and the lens 12 of positive refractive power of GaAs (Fl. Nos. 18-19).

[0349] Table 6:

[0350] ASP aspherical surface

[0351] Fl. No. 1 - 6 Lens 2

[0352] Fl. No. 7 Intermediate image 16

[0353] Fl. No. 8 - 11 front half 6

[0354] Fl. No. 12 - 13 diffuser lens 18

[0355] Fl. No. 16 - 19 rear half of turnaround 7

[0356] Fl. No. 21 - 22 detector window 19

[0357] Bottle No. 23 cold blend 20

[0358] Fl. No. 24 Image 17 or FPA (Focal Plane Array)

[0359] Fl. No. Radius Thickness Material

[0360] 1 : 63.02937 4.00 Ge

[0361] 2: -63.13928 2.57

[0362] ASP: A :0.189030E-04 B :-.455008E-07 C :0.111301 E-09 D :-.147047E-12 3: 28.97969 2.50 ZnS

[0363] 4: 11.47970 4.02

[0364] 5: 52.43516 3.00 Ge

[0365] ASP: A :-.433845E-06 B :-.412433E-07 C :-.202375E-08 D :0.299389E-10

[0366] 6: 67.48971 3.85

[0367] 7: INFINITY 8.85

[0368] 8: -23.53583 2.50 ZnS

[0369] 9: -127.83322 2.40

[0370] 10: -37.68016 4.00 Ge

[0371] 11 : -22.77495 2.50

[0372] ASP: A :0.168089E-05 B :-.131893E-07 C :0.740219E-10 D :-.194065E-12

[0373] 12: INFINITY 3.00

[0374] 13: INFINITY 1.00

[0375] 14: INFINITY 15.00

[0376] 15: INFINITY 16.63

[0377] 16: 78.48136 2.00 ZnS

[0378] 17: 34.48043 0.27

[0379] 18: 36.40406 3.00 GaAS

[0380] ASP: A :-.514623E-05 B :-.281755E-08 C :0.976406E-10 D :-.468252E-12

[0381] 19: -321.81640 0.60

[0382] 20: INFINITY 2.50

[0383] 21 : INFINITY 1.00 Ge

[0384] 22: INFINITY 1.57

[0385] 23: INFINITY 20.00

[0386] 24: INFINITY 0.00

[0387] A possible embodiment of the configuration of the optical device 1 shown in Figure 4 in the side beam path 10 or the MWIR path is given by Table 7.

[0388] Table 7:

[0389] ASP aspherical surface

[0390] Fl. No. 1 - 6 Lens 2

[0391] Fl. No. 7 Intermediate image 16

[0392] Fl. No. 8 - 11 front half 6

[0393] Fl. No. 12 - 13 diffuser lens 18

[0394] Fl. No. 15 Front surface of the beam splitter device 9

[0395] Fl. No. 17 - 18 rear half of turnaround 7

[0396] Fl. No. 19 - 20 detector window 19

[0397] Fl. No. 21 Cold aperture 20 Fl. No. 22 Image 17 or FPA (Focal Plane Array

[0398] Fl. No. Radius Thickness Material

[0399] 1 : 63.02937 4.00 Ge

[0400] 2: -63.13928 2.57

[0401] ASP: A: 0.189030E-04 B: -.455008E-07 C: 0.1 11301 E-09 D: -.147047E-12

[0402] 3: 28.97969 2.50 ZnS

[0403] 4: 11.47970 4.02

[0404] 5: 52.43516 3.00 Ge

[0405] ASP: A: -.433845E-06 B: -.412433E-07 C: -.202375E-08 D: 0.299389E-10

[0406] 6: 67.48971 3.85

[0407] 7: INFINITY 8.85

[0408] 8: -23.53583 2.50 ZnS

[0409] 9: -127.83322 2.40

[0410] 10: -37.68016 4.00 Ge

[0411] 11 : -22.77495 2.50

[0412] ASP: A: 0.168089E-05 B: -.131893E-07 C: 0.740219E-10 D: -.194065E-12

[0413] 12: INFINITY 3.00 Ge

[0414] 13: -62.00000 1.00

[0415] 14: INFINITY 15.00

[0416] 15: INFINITY 15.50

[0417] 16: INFINITY 2.50

[0418] 17: 60.31137 3.50 Si

[0419] ASP: A: -.588522E-05 B: 0.231773E-07 C: -.181798E-09 D: 0.629241 E-12

[0420] 18: -253.39544 7.50

[0421] 19: INFINITY 1 .00 Ge

[0422] 20: INFINITY 1 .56

[0423] 21 : INFINITY 16.00

[0424] 22: INFINITY 0.00

[0425] List of reference symbols:

[0426] 1 optical device

[0427] 2 lens

[0428] 3 reversing device

[0429] 4 Beam path

[0430] 5 Radiation

[0431] 6 front reversing half

[0432] 7 rear reversal half

[0433] 8 Air gap

[0434] 9 Beam splitter device

[0435] 10 Side beam path

[0436] 11 first detector device

[0437] 12 lenses

[0438] 12a Diverging lens

[0439] 12b Converging lens

[0440] 13 Direction of radiation propagation

[0441] 14 second rear reversal half

[0442] 15 second detector device

[0443] 16 Intermediate image

[0444] 17 Image

[0445] 18 Diffuser lens

[0446] 19 detector windows

[0447] 20 cold aperture

[0448] 30 first operating mode block

[0449] 31 second operating mode block

[0450] 32 beam splitting block

[0451] 33 Decoupling block

Claims

Patent claims:

1. Optical device (1) with an objective lens (2) and an optical reversing device (3) which are arranged along a beam path (4) of a radiation (5), characterized in that the reversing device (3) has a front reversing half (6) and at least one rear reversing half (7) spaced apart from the front reversing half (6) along the beam path (4), wherein an air gap (8) is formed between the front reversing half (6) and the rear reversing half (7), into which air gap a beam splitter device (9) can be introduced in such a way that the radiation (5) can be at least partially coupled out of the beam path (4) into a side beam path (10).

2. Optical device (1) according to claim 1, characterized in that the objective (2) and the front reversing half (6) have a plurality of lenses (12), wherein lenses (12b) with positive refractive power are formed partly or entirely from germanium and lenses (12a) with negative refractive power are formed partly or entirely from zinc sulfide.

3. Optical device (1) according to claim 1 or 2, characterized in that a first detector device (11) is provided for detecting the radiation (5) and is arranged in the beam path (4) behind the reversing device (3).

4. Optical device (1) according to one of claims 1 to 3, characterized in that at least one diffuser lens (18) is provided and can be introduced, preferably pivoted, into the air gap (8) in such a way that an image of an object point is defocused by the diffuser lens (18).

5. Optical device (1) according to one of claims 1 to 4, characterized in that a second rear reversing half (14) is provided and arranged in the side beam path (10).

6. Optical device (1) according to one of claims 1 to 5, characterized in that the beam splitter device (9) has a spectral splitter, which is designed in particular as a splitter plate, and which reflects a first spectral range of the radiation (5) and transmits a second spectral range of the radiation (5).

7. Optical device (1) according to claim 6, characterized in that the first spectral range, preferably exclusively, comprises an MWIR spectrum, in particular a wavelength range of the radiation from 3 pm to 6 pm, preferably 3.5 pm to 5 pm, and / or the second spectral range, preferably exclusively, comprises an LWIR spectrum, in particular a wavelength range of the radiation from 7 pm to 13 pm, preferably 8 pm to 13 pm.

8. Optical device (1) according to one of claims 1 to 7, characterized in that a first operating mode is provided, wherein in the first operating mode only the air gap (8) is arranged between the front reversing half (6) and the rear reversing half (7).

9. Optical device (1) according to claim 8, characterized in that in the first operating mode, the rear reversing half (7) has, preferably exclusively, two lenses (12), in which a diverging lens (12a) is arranged in front of a converging lens (12b) in a propagation direction (13) of the radiation (4).

10. Optical device (1) according to one of claims 1 to 9, characterized in that a second operating mode is provided, wherein in the second operating mode the beam splitter device (9) is present as part of the optical device (1) and is arranged such that the radiation (5) is at least partially coupled out of the beam path (4) into the side beam path (10) and a second detector device (15) for detecting the coupled-out radiation (5) is present and is arranged in the side beam path (10).

11. Optical device (1) according to one of claims 1 to 10, characterized in that the beam splitter device (9) comprises a zinc sulfide, preferably is formed from zinc sulfide.

12. Optical device (1) according to claim 10 or 11, characterized in that in the second operating mode, the rear reversing half (7) and / or the second rear reversing half (14) is / are each formed from a lens (12) with positive refractive power, which is adapted to the respective spectral range.

13. Optical device (1) according to one of claims 1 to 12, characterized in that the beam splitter device (9) is arranged at an angle of 40° to 50°, preferably 44.5° to 45.5°, tilted to the beam path (4).

14. Optical device (1) according to claim 13, characterized in that at least one image error caused by the tilting of the beam splitter (9) is partially or exclusively compensated by a decentering of a first group consisting of the rear reversing half (7) and the first detector device (11) and / or by a decentering of a second group consisting of the second rear reversing half (14) and the second detector device (15).

15. Method for imaging radiation (5), using an objective lens (2) and an optical reversing device (3) which are arranged along a beam path (4) of the radiation (5), characterized in that in a first operating mode the radiation (5) is imaged after the reversing device (3) onto a first detector device (11), and in a second operating mode a beam splitter device (9) is introduced between a front reversing half (6) and a rear reversing half (7) of the reversing device (3) in such a way that the radiation (5) is at least partially coupled out of the beam path (4) into a side beam path (10).

Images