OPTICAL FLEX SPECTRUM DETECTOR

Abstract

An optical device may include a separation element for separating an optical signal into a plurality of spectral bands that are spatially or angularly separated along a band separation direction. Spectral regions may differ between each spectral band of the plurality of spectral bands. The optical device may include a dispersive element comprising a plurality of dispersive regions. A dispersive region of the plurality of dispersive regions may disperse spectral components of a spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band. The optical device may include a plurality of optical elements. An optical element of the plurality of optical elements may image the dispersed spectral band in association with imaging the spectral band onto a detector surface.-area of a detector array. The optical device may include the detector array comprising the detector surface.

Description

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This patent application claims priority to U.S. Provisional Patent Application No. 63 / 620,080, filed January 11, 2024, entitled "FLEX SPECTRUM SPECTROMETRY." The disclosure of the prior application is considered part of this patent application and is incorporated by reference. TECHNICAL FIELD

[0002] The present disclosure generally relates to an optical detector and an optical flex spectrum detector. BACKGROUND

[0003] In spectrometry, a full-spectrum response is conventionally dispersed such that the dispersed spectrum has the form of a continuous elongated beam (with a large width-to-height aspect ratio) formed of dispersed spectral bands. Conventionally, the dispersed spectral bands are arranged in a "linear" one-dimensional (1D) sequence from one edge of a beam to another edge of the beam, either without any discontinuity or with only one spectral band imaged in a direction perpendicular to the direction of dispersion, for each detector pixel position along the direction of dispersion. When performing spectroscopy, it is generally desirable to detect a response from a sample with high sensitivity and high resolution across the full spectrum (e.g.,for Raman spectrometers over a spectral range of over 100 nanometers (nm) (in wavelength) or over 3000 reciprocal centimeters (cm. -1 ) (in wavenumbers)). SUMMARY

[0004] In some implementations, an optical device includes a separation element for separating an optical signal into a plurality of spectral bands that are spatially or angularly separated along a band separation direction, wherein spectral regions differ between each spectral band of the plurality of spectral bands; a dispersive element comprising a plurality of dispersive regions, wherein a dispersive region of the plurality of dispersive regions is configured to disperse spectral components of a spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band; a plurality of optical elements, wherein an optical element of the plurality of optical elements images the dispersed spectral band in association with imaging the spectral band onto a detector surface or-area of a detector array; and the detector array comprising the detector surface.

[0005] In some implementations, an optical device includes a separation element for separating an optical signal into a plurality of spectral bands having different spectral ranges and spatially or angularly separated along a band separation direction; a plurality of optical elements, wherein an optical element of the plurality of optical elements manipulates a spectral band of the plurality of spectral bands in association with imaging the spectral band onto a detector surface or region; and a detector array comprising the detector surface.

[0006] In some implementations, a method includes separating, by a separating element of an optical device, an optical signal into a plurality of spectral bands, each having a different spectral range and spatially or angularly separated along a band separation direction; dispersing, by a dispersing element of the optical device, spectral components of a spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band; and manipulating, by an optical element of the optical device, the dispersed spectral band in association with imaging the spectral band onto a detector area of a detector array of the optical device. BRIEF DESCRIPTION OF THE DRAWINGS Fig.1 is a diagram illustrating examples associated with an example implementation of an optical flex-spectrum detector described herein. Fig. Figure 2 illustrates an example associated with the optical device that provides flexible segmentation and arrangement of a full spectrum. Fig. 3 and Fig. 4 are graphs associated with an increase in dynamic range and sensitivity as enabled by an optical device described herein. Fig. 5-7 are diagrams illustrating example implementations of a separator described here. Fig. Figure 8 is a flow diagram of an example process associated with an optical flex spectrum detector described herein. DETAILED DESCRIPTION

[0007] The following detailed description of example implementations refers to the accompanying drawings. The same reference numerals in different drawings may refer to the same or similar elements.

[0008] In spectrometry, a spectrograph is conventionally designed to provide light as a single, non-segmented, linear optical beam containing a full spectral range, which is interrogated by the spectrograph at a dispersive element of the spectrograph. The dispersive element disperses the light, and the dispersed light is projected onto a detector of the spectrograph as a continuous, non-segmented, linear image.Here, the dispersed spectrum classically takes the form of a continuous, elongated beam (with a large width-to-height aspect ratio) formed of dispersed spectral components arranged in a "linear" 1D sequence from one edge of a beam to another edge of the beam, either without any discontinuity or with only one spectral component imaged in a direction perpendicular to a direction of dispersion, for each detector pixel position along the dispersion direction. When performing spectroscopy, it is generally desirable to detect a response from a sample with high sensitivity and high resolution over the full spectrum (e.g., for Raman spectrometers, over a spectral range of over 100 nanometers (nm) (in wavelength) or over 3000 reciprocal centimeters (cm). -1) (in wavenumbers)). However, in practice, this is difficult to implement efficiently. For example, if a highly sensitive and high-resolution detector array across a full spectrum is required, the physical design of the detector would have to accommodate a large width-to-height aspect ratio, resulting in an inefficient use of physical space in a spectrometer system. Accordingly, it would be advantageous to discard the conventional 1D shape of the dispersed spectrum and avoid the large aspect ratio of the detector, and be compatible with more typical 2D imaging detector arrays.

[0009] Furthermore, any dispersed spectrum has two important attributes: spectral range and spectral resolution. These attributes are at odds with each other for a fixed physical spectrum width. That is, for a given spectral range, there is a given spectral resolution. Increasing the resolution results in an increased spectral width for a fixed spectral range or a reduced spectral range for a fixed spectral width. These limitations exist for a 1D spectrum imaged on a detector. When performing spectroscopy, it is common for all spectral bands within the full-spectrum response to nominally have the same degree of sensitivity and resolution.However, most conventional spectroscopy systems aim to identify specific characteristics for which one or more particular spectral bands can provide more useful identification information, while other spectral bands can provide minimal identification information. This can lead to poor detector utilization if all spectral bands have the same sensitivity and resolution. Accordingly, it would be advantageous to provide greater sensitivity and resolution for spectral bands that provide more useful identification information and lower sensitivity and resolution for spectral bands that provide less useful identification information. Analogously, some spectral bands of the full spectrum may not provide any useful information at all, and therefore it would be advantageous to avoid imaging these spectral bands on the detector.

[0010] A conventional two-dimensional (2D) technique can be used in some cases to split a full spectrum into multiple beams (e.g., using a beam splitter), each containing the full spectral range. Then, different spectral range portions of each beam are imaged onto different detectors. Note that according to this conventional 2D technique, each beam contains the full spectrum at a fraction of the original power, and only a fraction of different spectral bands from each beam are then imaged onto a detector. This wastes power because the original power is split into each full-spectrum beam, and then the portions of each beam not imaged onto the detector are wasted.Thus, even those spectral regions that are mapped onto a section of the detector contain only a fraction of the original power in that spectral region. Wasted power also reduces sensitivity. Accordingly, it would be advantageous to map as much power as possible from the full spectrum onto the detector.

[0011] Implementations described here provide techniques and apparatus for measuring spectral responses in which a full-spectrum response can be divided into spectral bands (e.g., subspectra of any spectral range, resolution, or dynamic range), and each spectral band can be directed by dispersion and to a desired physical location on a detector array while preserving the power of the full-spectrum response. In other words, the techniques and apparatus described here can be implemented to separate a full-spectral response into a group of distinct spectral bands (e.g., subspectra) in wavelength or wavenumber with minimal power loss, and these spectral bands can then be independently manipulated or rearranged prior to spectral dispersion and imaging onto a detector (e.g., a 2D detector).The techniques and devices described here avoid power loss when splitting the full-spectrum response; decouple the bandwidth, resolution, and dynamic range limitations for each spectral band; increase the efficiency with respect to the use of a 2D detector and enable a more compact spectrograph.

[0012] The techniques and devices described here enable a comparatively more compact spectrograph by separating a full spectrum of incident light into spectral bands without any loss of power (apart from power loss caused by non-idealities of optical components that perform the separation function) and spatially rearranging the spectral bands (e.g., in a stack) before forwarding the spectral bands to a dispersive element. Such a design can enable higher optical resolution per spectral band from the dispersive element and, in some designs, allow a reduced size of the dispersive element in a dispersion direction. After dispersion, the dispersed spectral bands are projected and imaged onto a 2D detector array (e.g.,in a stack), enabling higher detector resolution and increasing the efficiency in terms of using an active area of the detector array.

[0013] The techniques and devices described herein involve spectral banding at a front end that splits a full spectral region prior to dispersion into multiple spectral bands (e.g., a set of adjacent, consecutive, or distinct spectral regions). In some implementations, the spectral bands may not overlap, or may partially (e.g., minimally) overlap, or may have almost no overlap (e.g., to allow for redundancy or manufacturing tolerance when attempting to create non-overlapping or adjacent spectral bands). In some implementations, the spectral bands may be rearranged in space and stacked onto a dispersive element in a non-dispersive direction (e.g., a direction perpendicular to the dispersion direction), creating a 2D array of spectral bands. In some implementations, the dispersive element may have multiple dispersive regions (e.g.,(each with different dispersive properties) that can be assigned to the spectral bands incident on it. Each dispersive region of the dispersive element can thus disperse and redirect the light incident on it independently of the other dispersive regions.

[0014] After dispersion, the spatial arrangement of the dispersed spectral bands can be maintained or further rearranged while the dispersed spectral bands are directed onto a detector array. In some implementations, for example, the dispersed spectral bands can be arranged in space and stacked onto a 2D detector array in a band separation direction. The spectral bands can be rearranged in different ways (e.g., depending on the chosen spectral range bins and resolution targets). In general, the number of spectral bands, the spectral ranges of the spectral bands, and the spectral resolutions of the spectral bands can be freely and independently adjusted according to a desired performance target for a given application (e.g., Raman, time-gated Raman, spatially offset Raman spectroscopy (SORS), fluorescence, or the like).For example, a spectrum formed from the sum of all spectral bands may be discontinuous (e.g., interrupted by one or more gaps) or may have different spectral resolutions for different subspectra. Additionally or alternatively, the dynamic range and sensitivity desired for measuring each spectral band can be freely adjusted and independent of the other spectral bands by controlling and / or regulating the "height" (e.g., in a direction orthogonal to the dispersion direction) at which each spectral band is imaged onto the detector.While increasing the detector area illuminated by a particular spectral band does not change the total amount of photons in that spectral band, increasing the detector area increases the dynamic range that can be achieved for that spectral band and increases a saturation limit of the detector for wavelengths in that spectral band because the photons are spread across more pixels of the detector. In some implementations, the techniques and devices described here enable the removal of one or more spectral bands (e.g., one or more spectral bands that are not of interest). For example, one or more spectral bands can be removed from an image on the detector during spectrum splitting, during dispersion, or during spatial or angular rearrangement (e.g., before or after dispersion).

[0015] It should be noted that the techniques and devices described here enable full-spectrum segmentation in a different way than the conventional 2D technique described above. In some implementations, the full spectrum is divided into spectral bands located at different wavelengths / wavenumbers, which are then spatially rearranged to create a 2D array in which multiple spectral bands (which together cover the full spectral range and may contain nearly all of the power of the original spectrum) are stacked in a direction perpendicular to the dispersion direction. With such an array, higher resolution can be achieved compared to a 1D array (i.e., on a 1D detector) of the same width.For comparison, achieving the same full spectral range with increased resolution using a linear 1D response would require a detector with a spectral dispersion dimension increased by a factor equivalent to the number of generated spectral bands (e.g., assuming that all spectral bands have the same width and cover the same spectral range). Compared to the conventional 2D technique, the power loss is minimal because the full spectrum has been divided into separate, (optionally) non-overlapping spectral bands that contain almost all of the full spectrum's power. This flex-spectrum spectrometry technique allows for maximum utilization of the active area of a detector, which can be a rectangular 2D detector array (e.g., with a low width-to-height ratio).In some implementations, the full spectrum can be separated into separate non-overlapping spectral bands that are spatially rearranged to be stacked in alignment with an active area of a low-aspect ratio 2D detector array.

[0016] For the same physical size as a conventional 1D solution, the techniques and devices described here can achieve higher resolution and / or cover a wider spectral range. Alternatively, the techniques and devices described here can achieve the same performance with a reduced width of the detector in the dispersion direction, which is typically the largest dimension of the detector used in spectrometry, at a fraction of the physical size of the conventional 1D technique. Segmenting the spectrum to reduce the width while adding height from the rearrangement of the segmented spectral bands in a direction perpendicular to the dispersion direction (i.e., the band separation direction) results in an advantageous detector geometry in terms of enabling a spectrometer or spectrometry system with a compact size (e.g.,volume) or in terms of compatibility with a wider range of commercially available detector arrays with large pixel counts (e.g., SPAD arrays). Adding detector height to cover the additional spectral bands results in little or no increase in spectrometer height, whereas reducing detector width results in a significant reduction in footprint due to lower angular dispersion of the dispersed subspectra and their smaller width at a single detector plane. As a result of the reduced detector width, the sizes of optical and mechanical components within the spectrometer are also reduced, resulting in a reduction in the size, weight, and (potentially) power consumption of the spectrometer system.

[0017] As described above, the techniques and devices described herein can achieve higher resolution and / or cover a larger spectral range for a given detector width along the dispersion direction. Performance attributes of a spectrometer are no longer fixed or limited by the detector width. Adding a second dimension to the spectral array enables this flexibility. The techniques and devices described here enable varying the detection dynamic range and sensitivity across the full spectral range. Because the spectrum is segmented, each spectral band can be adjusted to cover a specific height (i.e., a number of pixels in the band separation direction) on an active area of the detector.Therefore, the detection dynamic range and sensitivity (which scales with the height of a spectral component on the active area of the detector) can be modulated across the different spectral bands, for example to account for the relative importance of the different spectral bands in a spectrometry measurement.

[0018] Fig. 1 is a diagram illustrating an example implementation of an optical flex-spectrum detector described herein (referred to herein as optical device 100). As in Fig.1, an optical source 145 emits source light 150 (e.g., a laser beam) that is incident on a sample 155. An optical signal 160 emerging from the sample 155 (e.g., a modified transmitted signal from the optical source 145, a signal generated by the sample 155 as a result of excitation by the source light 150, or the like) includes spectral information (e.g., a spectral response) that is directed to the optical device 100. As shown in Fig. 1, the optical device 100 comprises a separation element 102, a dispersive element 104, a plurality of optical elements 106 (e.g., comprising an optical element 106a, an optical element 106b, and an optical element 106c), and a detector array 108 comprising a set of detector surfaces 110 (e.g., detector surface 110a, detector surface 110b, detector surface 110c). The upper diagram in Fig.1 illustrates an example of a view of the optical device 100 along a dispersion direction (i.e., a direction along which the dispersive element 104 disperses spectral bands 165, as described below), while the lower diagram in Fig. 1 illustrates an example of a view of the optical device 100 along a band separation direction (i.e., a direction along which the separation element 102 separates the optical signal 160 into a plurality of spectral bands 165, as described below).

[0019] The separation element 102 includes one or more elements for separating the optical signal 160 into a plurality of spectral bands 165. That is, the separation element 102 includes one or more elements that segment (e.g., by spectral range) and rearrange (e.g., spatially / angularly) the spectral response of the sample 155 into spatially and / or angularly rearranged spectral bands (e.g., spectral band 165a, spectral band 165b, spectral band 165c, and spectral band 165d). In some implementations, the direction along which the separation element 102 spatially or angularly separates the optical signal 160 into the plurality of spectral bands 165 is referred to as the band separation direction. In some implementations, the band separation direction is perpendicular to a dispersion direction (e.g., a direction along which the dispersive element 104 disperses the spectral bands 165).It should be noted that while the band separation direction perpendicular to the dispersion direction may be used for practical purposes, in some implementations, a geometry may be used where the band separation direction is not perpendicular to the dispersion direction (e.g., depending on a detector geometry). In some implementations, the separation of the optical signal 160 (e.g., the segmentation and rearrangement of the spectrum) is performed in a single direction—the band separation direction. For example, the separation element 102 may change an angle of wavelengths of the optical signal 160 to create a continuous spatial spectrum propagating in the band separation direction.

[0020] The separator 102 may be configured to provide any number of spectral bands with different properties (e.g., physical size and orientation in space, spectral range, and / or spectral width). In some implementations, the spectral ranges differ between each spectral band 165 of the plurality of spectral bands 165. In some implementations, the spectral bands 165 within the plurality of spectral bands 165 may substantially not overlap (e.g., such that each spectral band 165 covers a substantially different frequency range). Such an implementation may, for example, be used to maximize a spectral range covered by the banding of the optical signal 160 provided by the separator 102. In some such implementations, an overlap between a given pair of adjacent spectral bands 165 may be small (e.g.,a maximum overlap in a range of about 2% to about 10%). Such overlap may be used, for example, to avoid gaps between spectral bands 165 that might otherwise arise due to design or manufacturing non-idealities. Additionally or alternatively, spectral bands 165 may substantially overlap in the plurality of spectral bands 165 (e.g., an overlap in the frequency domain that is greater than about 10%) to provide significant spectral redundancy. For example, an application may require that the same subband spectral range (e.g., an overlap of about 100%) be detected by two different detector areas 110 of the detector array 108 (e.g.,if the two detector surfaces 110 have different detector properties, if a power in each “identical” spectral band 165 is intentionally made different upon incidence on a respective dedicated detector surface 110, or the like).

[0021] In some implementations, the separation element 12 may be configured such that the optical power differs between spectral bands 165 (e.g., such that an optical power of a given spectral band 165 is controlled and / or regulated to a desired degree or intentionally differs from an optical power of another spectral band 165). Such an implementation may be used, for example, when different detector surfaces 120 have different optical input power saturation levels (or thresholds) and it is desirable for the different detector surfaces 120 to behave similarly. As another example, such an implementation may be used when using a detector surface 120 with different input power levels is desirable in order to examine the detector surface 120 in different optical input power saturation regimes (e.g.,several spectral bands 165 with the same spectral range, but with different optical power, could be sent to several nominally identical detector surfaces 120).

[0022] In some implementations, the separator 102 may segment the optical signal 160 into spectral bands with no power loss (e.g., except for power losses caused by component non-idealities). It should be noted that conventional techniques are based on power splitting rather than spectral separation. In other words, the conventional techniques split an optical signal into N (N > 1) approximately equivalent sub-beams, with each sub-beam having 1 / N-th of the power from each spectral band of the full spectrum. Conversely, the separation provided by the separator 102 separates the optical signal 160 into the plurality of spectral bands 165 with all the power from its respective band and no power from the other bands (within reasonable component non-idealities).Accordingly, the separation provided by the separation element 102 preserves the power relevant to each spectral band, enabling increased throughput and thereby higher sensitivity for spectrometry. Additionally, preserving the power relevant to each spectral band enables increased measurement speed for spectrometry. For example, the SNR for a given detected spectral component (e.g., a Raman peak within a portion of the spectrum) for a given detection time (i.e., photon collection time) is approximately proportional to the square root of the number of detected Raman photons.For a given excitation pulse energy and a given number of excitation pulses (or equivalently, a given detection time window), comparatively more Raman photons reach the detector within this spectral component, and therefore, a higher SNR is achieved with spectral splitting (compared to power splitting). This means that for the same SNR, spectral splitting requires a smaller number of pulses and therefore a reduced detection time window, which is equivalent to an increase in measurement speed.

[0023] The dispersive element 104 comprises one or more elements for dispersing spectral components of the spectral bands 165 to form dispersed spectral bands 165. That is, the dispersive element 104 comprises one or more elements that disperse the spectral bands 165 (e.g., the spectral bands 165a to 165d) to form a plurality of dispersed spectral bands 165 (e.g., dispersed spectral band 165a, dispersed spectral band 165c, and dispersed spectral band 165d in the Fig.1). In some implementations, the dispersive element 104 may include one or more elements capable of spatially separating incoming light into different spectral components (e.g., wavelengths). For example, the dispersive element 104 may include a diffraction grating, a prism, or another wavelength-dispersive element. In one example implementation, the spatially separated spectral bands 165 are incident on a diffraction grating having spatially separated sections (which may or may not be contiguous), each section configured to operate on the corresponding incident spectral band 165. In some implementations, the direction along which the dispersive element 104 disperses a spectral band 165 is referred to as the dispersion direction. In some implementations, the dispersive element 104 comprises a plurality of dispersive regions (e.g.,to disperse a respective one of the plurality of spectral bands 165). In some implementations, the plurality of dispersive regions may be stacked along the band separation direction (e.g., perpendicular to the dispersion direction). In some implementations, a given dispersive region of the dispersive element 104 disperses a spectral band 165 incident thereon independently of the dispersion by other dispersive regions of the dispersive element 104. For example, in some implementations, the plurality of dispersive regions may be monolithically patterned (or mechanically tiled) on a single dispersive element 104, with each dispersive region having a respective (e.g., different) set of dispersive properties.

[0024] In operation, the dispersive element 104 serves to physically separate spectral components forming a given spectral band 165 such that the spectral components of the given spectral band 165 exit the dispersive element 104 at different angles and positions to form a dispersed spectral band 165. In some implementations, the dispersive regions of the dispersive element 104 may operate differently on each spectral band 165 to create dispersed spectral bands 165 with different optical properties (e.g., physical size and orientation in space, spectral range, spectral width, spectral resolution, or the like). For example, a given dispersive region of the dispersive element 104 may angularly and spatially segment or separate a continuous spatial spectrum into individual bands.In some implementations, the dispersive element 104 may define a spectral range of a given spectral band 165.

[0025] The plurality of optical elements 106 includes one or more elements for manipulating the dispersed spectral bands 165 in association with imaging the spectral bands 165 onto detector surfaces 110 of the detector array 108. In some implementations, the plurality of optical elements 106 includes an imaging subsystem for spectral bands 165 to be imaged onto the detector array 108. In some implementations, the plurality of optical elements 106 includes a plurality of elements capable of manipulating a position, a size, and / or an orientation / direction of spectral bands 165 to image one or more spectral bands 165 from the plurality of spectral bands 165 onto the detector array 108 and with a particular arrangement (e.g., as dictated by the size of the detector array 108 and / or performance attributes and / or functional criteria).For example, a given optical element 106 may include one or more lenses, prisms, wedges, mirrors, diffraction gratings, bulk optics, or the like, as well as combinations thereof. In some implementations, a given optical element 106 may maintain one or more properties (e.g., a spectral range, a spectral resolution, a detection dynamic range and sensitivity, a physical size, or a position on a plane of the detector array 108, or the like) of a given spectral band 165 and map such properties to a particular detector surface 110 of the detector array 108. Additionally or alternatively, a given optical element 106 may modify one or more properties of a given spectral band 165.For example, an optical element 106 may be configured to fill a width of the detector array 108 to achieve highest resolution and / or to determine a height of the detector array 108 used for each respective spectral band 165 (e.g., to control and / or regulate dynamic range and sensitivity). In some implementations, the plurality of optical elements 106 may serve to arrange the dispersed spectral bands 165 to optimize utilization of the detector array 108 (e.g., to maximize an area utilized on the detector array 108, to maximize optical resolution, to utilize a specific detector area 110 on the detector array 108 for a specific spectral band 165, or the like).For example, the plurality of optical elements 106 may expand the dispersed spectral bands 165 to match a width of the detector array 108 and stack each spectral band 165 into detector surfaces 110 with respective heights on the detector array 108. In some implementations, the plurality of optical elements 106 may manipulate the dispersed spectral band 165 (e.g., align, steer, focus, collimate, converge, expand, or the like) such that images of the spectral bands 165 are stacked along the band separation direction on a plane of the detector surface 110. For example, in some implementations, the plurality of optical elements 106 may provide spatial rearrangement of the plurality of spectral bands 165 on a plane of the detector surface 110. In some implementations, an optical element 106 in the plurality of optical elements 106 may manipulate a dispersed spectral band 165 such that (e.g.,B. expand) such that a size of the dispersed spectral band 165 along the dispersion direction matches a size of a detector surface 110 along the dispersion direction (e.g., a surface of the detector array 108 onto which the spectral band 165 is to be imaged). Analogously, in some implementations, the optical element 106 can manipulate (e.g., expand) the dispersed spectral band 165 such that a size of the dispersed spectral band 165 in the band separation direction matches a size of the detector surface 110 along the band separation direction. In this way, the spatial arrangement of the dispersed spectral bands 165 at the detector surface 110 can be controlled and / or regulated to maximize the use of a particular detector geometry (e.g., a rectangular 2D detector array 108).

[0026] The detector array 108 includes one or more detector surfaces 110 on which one or more of the spectral bands 165 are imaged. In some implementations, as in Fig.1, the detector surface 110 may comprise a plurality of detector surfaces 110 stacked along the band separation direction. In some implementations, the detector array 108 may comprise a 2D array (e.g., a 2D array of detector surfaces 110). Additionally or alternatively, the detector array 108 may comprise a plurality of 1D detector arrays (e.g., a plurality of 1D detector arrays stacked along the band separation direction). Such an implementation may, for example, extend detection capabilities (e.g., spectral range, spectral resolution, detection dynamic range, detection sensitivity, or the like) of the optical device 100. In some implementations, the detector array 108 may comprise a single-photon avalanche diode (SPAD) array (e.g., a high dynamic range, high sensitivity, and high temporal resolution (sub-nanosecond) SPAD array).Additionally or alternatively, the detector array 108 may include an array of time-resolved photon counting detectors (e.g., an array of areas capable of assigning a timestamp to each photon detected by a given area). Such detectors may also be referred to as time-binned photon counting detectors or time-tagged photon counting detectors. Alternatively, the detector array 118 may include a detector array including photon detectors using a different type of technology (e.g., an array of photon detectors that may or may not include time-resolved photon counting detectors). In some implementations, a size of a first detector area 110 of the plurality of detector areas 110 differs from the size of a second detector area 110 of the plurality of detector areas 110. In some implementations, a detector area 110 of the detector array 108 may be used for multiple spectral bands 165.The reuse of a detector surface 110 may be enabled, for example, by time-domain multiplexing in combination with an active element capable of selecting a spectral band 165 to be manipulated and imaged onto the given detector surface 110 at a given time.

[0027] In some implementations, a size of a first detector area 110 of the detector array 108 in the dispersion direction matches a size of a second detector area 110 of the detector array 108 in the dispersion direction, and a size of the first detector area 110 in the band separation direction differs from a size of the second detector area 110 in the band separation direction. In such an implementation, greater sensitivity is provided for a spectral band 165 imaged onto the first detector area 110 with the comparatively larger size. In this way, the dynamic range and sensitivity desired for measuring each spectral band 165 can be freely adjusted independently of the other spectral bands 165 by controlling and / or regulating the "height" in the band separation direction with which each spectral band 165 is imaged onto the detector array 108.While increasing the size of the detector area 110 illuminated by a particular spectral band 165 does not change the total amount of photons in that spectral band 165, the increase in size increases the dynamic range and sensitivity that can be achieved for that spectral band 165 (e.g., by reducing the effect of a preset “dead time” that occurs after a pixel detection event in SPAD arrays), and increases the saturation limit of the detector array 108 for wavelengths in that spectral band 165 because the photons are spread across more pixels of the detector array 108.

[0028] In the Fig.1, the separation element 102 provides four spectral bands 165 (i.e., four sub-spectra), three of which (e.g., spectral band 165a, spectral band 165c, and spectral band 165d) are directed to the dispersive element 104 to be dispersed and then manipulated by the respective optical elements 106 for imaging with three different geometries (e.g., different heights of each spectral band 165). An example of a resulting arrangement of the optical signal 160 into these three spectral bands 165 with different properties (e.g., height-dependent dynamic range and sensitivity, spectral range, covered spectral width, spectral resolution) is shown in Fig.1 and in Table 1 below. It should be noted that in this example, spectral band 165b is not imaged on detector array 108. That is, in some implementations, at least one spectral band 165 of the plurality of spectral bands 165 may not be imaged on any detector surface 110 of detector array 108. Such an implementation may be used, for example, when some portion (e.g., spectral band 165b) of the full spectrum does not need to be measured or detected. In some implementations, the ability to have such spectral gaps in detection at detector array 108 may enable improvement in one or more other attributes of the detected spectral bands 165 (e.g., increased resolution, redundancy, readout speed, or the like).Thus, in some implementations, a spectrum formed by a sum of a set of spectral bands 165 imaged on the detector array 108 is discontinuous (e.g., it includes one or more spectral gaps). In some implementations, an optical power of a given spectral band 165 of the plurality of spectral bands 165 at the detector array 108 is more than 90% of an optical power of the spectral band 165 before the separation element 102. That is, spectral bands 165 can be imaged on the detector array 108 with no or minimal power loss (apart from power loss caused by non-idealities of optical components performing the separation function).

[0029] It should be noted that since the spectral bands 165 can be stacked when imaged onto the detector array 108 (e.g., a 2D detector array), a required angular range of elements and optics of the optical device 100 in the dispersion direction is significantly reduced (e.g., compared to a conventional device using a comparatively longer 1D detector). This reduces the physical size of the optical device 100, enabling a more compact optical engine. Furthermore, the optical device 100 can be applied to many existing spectroscopy techniques. For example, the optical device 100 can be used for Raman and fluorescence spectroscopy, and the read time of the detector array 108 can be time-gated and / or correlated with exposure of the sample 155 to the source light 150.

[0030] Furthermore, according to the techniques described herein, in some implementations, a given spectral band 165 may be directed to any detector face 110 of the detector array 108. An active area of the detector array 108 need not have the same dimension as an area given by a sum of areas of all spectral bands 165 to be detected at the plane of the detector array 108. In some implementations, the spectral bands 165 may be arranged to match a width of the active area of the detector array 108, and a scanning mechanism may be used to move the spectral bands 165 in the band separation direction so that they fall on the detector face 110, or to move the detector array 108 in the band separation direction so that it falls within the field of view of the desired spectral band(s) 165. This may allow the use of a detector array 108 with reduced size (e.g.a 1D array with reduced size or a 2D array with fewer detector areas) whose width is determined by the width of a single spectral band 165 to measure the full spectrum (e.g. a sum of all spectral bands 165).

[0031] In some implementations, one or more elements of the optical device 100 may be configured statically (e.g., using conventional optics). Additionally or alternatively, one or more elements of the optical device 100 may be dynamically configured to dynamically configure, for example, the number of spectral bands 165 generated, a spectral range of each spectral band 165, a dynamic range and sensitivity (or height on the detector array 108) applied to each spectral band 165, and / or a position at which each spectral band 165 is imaged on the detector array 108. A dynamic configuration may allow different spectral bands 165 from different pulses to be imaged onto the detector array 108.In some implementations, a readout of one or more detector areas 110 of the detector array 108 may be performed using a variety of techniques, such as using a global shutter or a rolling shutter. Furthermore, in some implementations, one or more spectral bands 165 may be removed by the separator 102 (e.g., as shown in FIG. Fig. 1). Additionally or alternatively, one or more other elements of the optical device 10 may be configured to remove one or more spectral bands 165 (e.g., such that the one or more spectral bands 165 are not imaged onto the detector array 108), such as the dispersive element 104 or one or more optical elements 106.

[0032] An optical resolution is given by the dispersive element 104 (e.g., a grating resolution) regardless of the characteristics of the detector array 108. A detector resolution is given by the detector array 108 (e.g., a pixel size of the detector array 108) and, analogously, is independent of the dispersive element 104. The system resolution combines the optical resolution and the detector resolution. In the optical device 100, a best result that can be achieved is the optical resolution, because even if better detector resolution is provided, the detector array 108 cannot sample with a higher resolution than through the dispersed spectral bands 165 provided by the dispersive element 104. In practice, one goal is to match the detector resolution to the optical resolution to avoid degradation of the optical resolution without having unnecessary pixels.In some implementations, a spectral resolution of a first spectral band 165 of the plurality of spectral bands 165 differs from a spectral resolution of a second spectral band 165 of the plurality of spectral bands 165.

[0033] A spectral range is defined by the range of wavenumbers or wavelengths contained in a particular spectral response, signal, band, or subspectra. The spectral range is analogous to a bandwidth in wavelengths. In the case of Raman spectroscopy, an example spectral range of the optical signal 160 may be more than about 100 nm (wavelength) or more than about 3000 cm -1(wavenumber). Furthermore, an example spectral range of a given spectral band 165 may be between approximately 400 and 700 wavenumbers. In some implementations, a spectral range of the first spectral band 165 of the plurality of spectral bands 165 may differ from a spectral range of a second spectral band 165 of the plurality of spectral bands 165.

[0034] The dynamic range is a range of values that can be reported by a set of pixels of the detector array 108 with respect to a particular wavelength / wavenumber in a spectral band 165. In some implementations, increasing the number of pixels per wavelength / wavenumber can increase the dynamic range for that wavelength / wavenumber (e.g., by reducing the impact of the reset "dead time" that occurs after a pixel detection event in SPAD arrays).

[0035] As mentioned above, Fig.1 is provided as an example. Other examples may differ from what is described with reference to Fig. 1. The number and arrangement of the Fig. 1 are provided as an example. In practice, additional elements, fewer elements, different elements or differently arranged elements than those shown in Fig. 1. Furthermore, two or more in Fig. 1 elements may be implemented within a single element or a single element in Fig. 1 may be implemented as multiple, distributed elements. Additionally or alternatively, a set of elements (e.g., one or more elements) that are Fig. 1, perform one or more functions that can be considered as performed by another set of elements shown in Fig. 1 are described as fulfilled.

[0036] Fig.Figure 2, in combination with Table 1 (below), illustrates an example associated with the optical device 100 that enables flexible segmentation and arrangement of a full spectrum. Fig.2, the spectral bands 165 are arranged such that the spectral bands 165 are imaged in a stack in the band separation direction (e.g., a direction perpendicular to the dispersion direction) at the detector array 108. As noted above, the spectral bands 165 may be arranged in various ways, for example, depending on a spectral range, a spectral resolution, and / or a detection dynamic range and sensitivity objective. In some implementations, a number and areas of the spectral bands 165 may be varied, and each spectral range, resolution, dynamic range, and / or sensitivity of each spectral band 165 may be adjusted independently of those of the other spectral bands 165 (e.g., for the purpose of meeting specific performance objectives for a given application). For example, portions of the full spectrum that do not need to be measured or detected (e.g.,spectral band 165b), may be skipped (e.g., avoided or rejected) in some implementations. As another example, specific pixels or detector areas 110 of detector array 108 that cannot or should not be used may be avoided. Table 1 Spectrum band # Relative importance for sample identification Detector area # Band height (pixels) (size of the sensor) Spectral range (wavenumbers) Spectral bandwidth (wavenumbers) Spectral resolution (wavenumbers) 165a Normal 110a 200 400-700 300 1.5 165b Not monitored N / A N / A 700-1100 400 N / A 165c High 110b 400 1100-1600 500 0.5 65d Low 110c 100 0-400 400 4

[0037] Table 1 shows a numerical example illustrating attributes of the different spectral bands 165 mapped onto a 2D detector array 108 comprising three detector surfaces 110, as shown in Fig.1. In this example, a height of an example detector surface 110 is 700 pixels and an example spectral range (expressed as a spectral shift from the excitation wavelength) is 0 to 1600 wavenumbers. Here, a fraction of the full spectrum, spectral band 165b, is not measured or monitored and therefore not imaged onto the detector array 108, while the remainder of the full spectrum is divided into spectral band 165a, spectral band 165c, and spectral band 165d with different spectral ranges, resolutions, dynamic ranges, and sensitivities (e.g., scaling with the height on the detector array 108, referred to as band height in Table 1) and imaged onto different detector surfaces 110 of the detector array 108.

[0038] As mentioned above, Fig. 2 provided as an example. Other examples may differ from what is described with reference to Fig. 2 is described.

[0039] Fig. 3 and Fig. 4 are graphs associated with an increase in dynamic range and sensitivity enabled by the optical device 100. In some implementations, dynamic range and sensitivity may be increased without changing the light collection and spectral separation at the front end. In one example implementation, a back-end imaging optic (e.g., one or more optical elements 106) may be configured to image energy in a spectral band 165 with a different, larger height onto the detector array 108, at the expense of a reduced height or number of other spectral bands 165 for a fixed-size detector area. Alternatively, in another example implementation, two or more spectral bands 165 may be configured identically (e.g., spectral band 165a and spectral band 165d in Fig.3) and power in these spectral bands 165 can be distributed equally.

[0040] In the Fig. 3, the spectral band 165c has twice the height of the spectral band 165a (e.g., 200 pixels versus 100 pixels) on the detector array 108 (e.g., a height of the detector surface 110 at which the spectral band 165c is imaged is twice that of the detector surface 110 at which the spectral band 165a is imaged). If all spectral bands 165 have the same energy (e.g., power or throughput), then the spectral band 165c would have a pulse energy per pixel reduced by a factor of 2 compared to the spectral band 165a (and the spectral band 165d). The effect of reducing the energy density (e.g., energy per pixel) on the detector array 108 is illustrated in the Fig.4 for two channel sizes: a spectral channel with a specific width and height of 100 pixels and a spectral channel with a specific width and height of 200 pixels. As shown in Fig. 4, the higher channel (i.e., the spectral channel with a height of 200 pixels) has a larger dynamic range for count detection, resulting in increased sensitivity. In the Fig. 4, if the pulse energy were further increased, the detected counts per pulse would eventually saturate the detector array 108, meaning that the detector array 108 would not be able to detect more counts despite an increase in pulse energy. In some implementations, the sensitivity and saturation threshold can be increased by increasing the height (e.g., and the number of pixels) allocated to a particular spectral band 165.

[0041] In some implementations, a first spectral band 165x having a comparatively smaller bandwidth may be imaged on a first detector surface 110x of the detector array 108, and a second spectral band 165y having a comparatively larger bandwidth may be imaged on a second detector surface 110y of the detector array 108, while an overall width and pixel size (i.e., resolution) of the first detector surface 110x in the dispersion direction matches an overall width and pixel size (i.e., resolution) of the second detector surface 110y in the dispersion direction. In this way, if the optical resolution of a first spectral band 165x matches the optical resolution of a second spectral band 165y, the first spectral band 165x may be provided with a higher spectral resolution than the second spectral band 165y (e.g.,since each detector pixel receives fewer wavenumbers for the first spectral band 165x with the comparatively smaller bandwidth).

[0042] As mentioned above, Fig. 3 and Fig. 4 as examples. Other examples may differ from what is provided with reference to the Fig. 3 and Fig. 4 is described.

[0043] Fig.5-7 are diagrams illustrating example implementations of a separation element 102 described herein. In some implementations, as noted above, the separation element 102 may include one or more elements capable of spatially or angularly separating the optical signal 160 into a plurality of spectral bands 165 such that each spectral band 165 is spatially or angularly separated from other spectral bands 165. In some implementations, the separation element 102 may include a plurality of thin-film interference filters, each associated with a different spectral band 165 of the plurality of spectral bands 165. Fig. Figure 5 is a diagram illustrating an example implementation of a separation element 102 comprising a plurality of (e.g., four) thin-film interference filters 502. Additionally or alternatively, these may comprise a diffraction grating. Fig. 6 and Fig.7 are diagrams illustrating an example implementation of a separation element 102 including a diffraction grating 602. Additionally or alternatively, the separation element 102 may include one or more other types of optical elements.

[0044] In some implementations, light of the optical signal 160 having a wavelength near a boundary between two spectral bands 165 may be split by the separation element 102 such that respective portions of the light enter a plurality of spectral bands 165. Thus, in some implementations, a spectral component at or near a boundary between a first spectral band 165 of the plurality of spectral bands 165 and a second spectral band 165 of the plurality of spectral bands 165 may be split such that a first portion of the spectral component is in the first spectral band 165 and a second portion of the spectral component is in the second spectral band 165. Here, the sum of the power of the first portion and the power of the second portion is a total power of the spectral component.

[0045] In the Fig.5, the optical signal 160 includes a full spectrum emanating from the sample 155 (e.g., as in Fig. 1). Here, each thin-film interference filter 502 reflects only a fraction (e.g., a spectral band 165) of the full spectrum and transmits the rest. In some implementations, as in Fig. 5, a sequence of several (e.g., four) interference filters 502, followed by a mirror 504, divides the full spectrum into several (e.g., five) spatially separated spectral bands 165, which are then incident on a focusing lens 506 to convert the spatial separation (e.g., offset) into an angular separation (e.g., angle) of the different spectral bands 165. The spectral bands 165 can then be imaged onto a plane for further optical processing. In connection with the Fig.1, the spatially / angularly separated spectral bands 165 are then directed onto the dispersive element 104.

[0046] In the Fig. 6 and Fig. 7, the optical signal 160 including the full spectrum emanating from the sample 155 (e.g. as in Fig. 2) collimated by a lens 604 and then directed onto a diffraction grating 602, which separates the incident light into different spectral components (e.g., wavelengths). The diffracted light emerging from the diffraction grating 602 is then focused and imaged by a lens 606 to produce spatially and angularly separated spectral bands 165. The Fig.The imaging system shown in Figure 7 includes a wedge 702 and prisms 704a and 704b, which are designed to change the beam path lengths and propagation angles of the rays of the spectral bands 165 in such a way that the emerging spectral rays appear to come from a single focal plane, but from different angles (e.g. analogous to the Fig. 5). In connection with the Fig. 1, the spatially / angularly separated spectral bands 165 are then directed onto the dispersive element 104.

[0047] As mentioned above, Fig. 5-7 as examples. Other examples may differ from what is described with reference to Fig. 5-7. The number and arrangement of the Fig.The elements shown in Figures 5-7 are provided as examples. In practice, additional elements, fewer elements, different elements, or differently arranged elements than those shown in Fig. 5-7 shown. Furthermore, two or more in Fig. 5-7 elements can be implemented within a single element or a single element in Fig. 5-7 may be implemented as multiple distributed elements. Additionally or alternatively, a set of elements (e.g., one or more elements) contained in Fig. 5-7, perform one or more functions that can be considered as performed by another set of elements shown in Fig. 5-7 are described as fulfilled.

[0048] Fig.Figure 8 is a flowchart of an example process 800 associated with a flex-spectrum optical detector described herein. In some implementations, one or more process blocks of Fig. 8 by one or more elements of an optical device (e.g., the optical device 100).

[0049] As in Fig. 8, a process 800 may include separating an optical signal into a plurality of spectral bands, each having a different spectral range and spatially or angularly separated along a band separation direction (block 810). For example, a separation element 102 of the optical device 100 may separate an optical signal 160 into a plurality of spectral bands 165, each having a different spectral range and spatially or angularly separated along a band separation direction, as described above.

[0050] As in Fig. 8, the process 800 may include dispersing spectral components of a spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band (block 820). For example, a dispersive element 104 of the optical device 100 may disperse spectral components of a spectral band 165 of the plurality of spectral bands 165 along a dispersion direction to form a dispersed spectral band 165, as described above.

[0051] As in Fig.8, process 800 may include manipulating the dispersed spectral band in association with imaging the spectral band onto a detector surface of a detector array of the optical device (block 830). For example, an optical element 106 of the optical device 100 may manipulate the dispersed spectral band 165 in association with imaging the spectral band 165 onto a detector surface 110 of a detector array 108 of the optical device 100, as described above.

[0052] Process 800 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. In a first implementation, a property (e.g., an optical resolution) of a first dispersed spectral band 165 of the plurality of dispersed spectral bands 165 differs from a property of a second dispersed spectral band 165 of the plurality of dispersed spectral bands 165.

[0053] In some implementations, at least one of a position, a size, or an orientation (direction) of a manipulated dispersed spectral band 165 formed by the manipulation of the dispersed spectral band 165 differs from a position, a size, or an orientation of a second manipulated dispersed spectral band 165 formed by the manipulation of a second dispersed spectral band 165.

[0054] In some implementations, each separate spectral band 165 may be dispersed by the dispersive element 104, while in other implementations, one or more spectral bands 165 separated from the optical signal 160 may be directed away from the dispersive element 104 and / or the detector array 118 (e.g., as described with respect to the spectral band 165b in Fig. 1).

[0055] Although Fig.8 shows example blocks of the process 800, in some implementations the process 800 includes additional blocks, fewer blocks, different blocks, or differently arranged blocks than those in Fig. 8. Additionally or alternatively, two or more of the blocks of process 800 may be performed in parallel.

[0056] The above disclosure provides illustration and description, but is not intended to be exhaustive or to limit implementations to the precise forms disclosed. Modifications and variations may be made in light of the above disclosure or may be learned from practice of implementations. Furthermore, any of the implementations described herein may be combined unless the above disclosure expressly provides a reason why one or more implementations may not be combined.

[0057] Although certain combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of various implementations. Indeed, many of these features may be combined in ways not expressly recited in the claims and / or disclosed in the specification. Although each dependent claim recited below may depend directly on only one claim, the disclosure of various implementations includes each dependent claim in combination with every other claim in the claim set. As used herein, language referring to "at least one of" a list of items refers to any combination of those items, including individual members.For example, “at least one of: a, b or c” is intended to cover a, b, c, ab, ac, bc and abc and any combination with multiples of the same element.

[0058] When a component or one or more components (e.g., an optical element or one or more optical elements) is described or claimed (within a single claim or across multiple claims) to perform or be configured to perform multiple operations, that language is intended to broadly cover a variety of architectures and environments. For example, unless explicitly claimed otherwise (e.g.,by the use of "first component" and "second component" or by other language that distinguishes components in the claims), this language is intended to cover, for example, a single component that performs or is configured to perform all of the operations, a group of components that collectively perform all of the operations or are configured to perform all of the operations, a first component that performs or is configured to perform a first operation and a second component that performs or is configured to perform a second operation, or any combination of components that perform the operations or are configured to perform the operations.For example, if a claim takes the form "one or more components configured to perform X; perform Y; and perform Z", that claim should be interpreted to mean "one or more components configured to perform X; one or more (possibly different) components configured to perform Y; and one or more (also possibly different) components configured to perform Z".

[0059] No element, act, or instruction used herein should be construed as essential or essential unless expressly described as such. In addition, as used herein, the articles "a" and "an" are intended to include one or more elements and may be used interchangeably with "one or more." Further, as used herein, the article "the" is intended to include one or more elements referred to in conjunction with the article "the" and may be used interchangeably with "the one or more." Further, as used herein, the term "set" is intended to include one or more elements (e.g., related elements, unrelated elements, or a combination of related and unrelated elements) and may be used interchangeably with "one or more."When only one element is meant, the phrase "merely a" or an analogous phrase is used. In addition, as used herein, the terms "comprises," "having," "having / comprising," or the like are open-ended terms. Further, the phrase "based on" is intended to mean "based at least in part on" unless expressly stated otherwise. In addition, as used herein, the term "or," when used in a sequence, is intended to be inclusive and may be used interchangeably with "and / or" unless expressly stated otherwise (e.g., when used in combination with "either" or "merely one of").Furthermore, for ease of description, spatially relative terms such as "beneath," "lower," "above," "upper," and the like may be used herein to describe the relationship of one element or feature to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device, facility, and / or element in use or operation in addition to the orientation depicted in the figures. The device may be oriented differently (rotated 90 degrees or in other orientations), and the spatially relative terms used herein may also be interpreted accordingly.

[0060] Further aspects, features and embodiments of the present disclosure are described under the following points: 1. An optical device comprising: a separating element for separating an optical signal into a plurality of spectral bands which are spatially or angularly separated along a band separation direction, wherein spectral ranges differ between each spectral band of the plurality of spectral bands; a dispersive element comprising a plurality of dispersive regions, wherein a dispersive region of the plurality of dispersive regions is configured to disperse spectral components of a spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band; a plurality of optical elements, wherein one optical element of the plurality of optical elements is configured to manipulate the dispersed spectral band in association with or in connection with imaging the spectral band onto a detector surface or region of a detector array; and the detector array that encompasses the detector area. 2. The optical device according to item 1, wherein the band separation direction is perpendicular to the dispersion direction. 3. An optical device according to item 1 or 2, wherein the plurality of spectral bands do not substantially overlap. 4. The optical device according to any one of items 1 to 3, wherein a spectral resolution of a first spectral band of the plurality of spectral bands differs from a spectral resolution of a second spectral band of the plurality of spectral bands. 5. The optical device according to any one of items 1 to 4, wherein a bandwidth of a first spectral band of the plurality of spectral bands differs from a bandwidth of a second spectral band of the plurality of spectral bands. 6. The optical device according to any one of items 1 to 5, wherein a spectrum formed by a sum of a set of spectral bands of the plurality of spectral bands imaged on the detector array is discontinuous. 7. Optical device according to one of items 1 to 6, wherein at least one spectral band of the plurality of spectral bands is not imaged onto any detector surface of the detector array. 8. The optical device according to any one of items 1 to 7, wherein an optical power of a spectral band of the plurality of spectral bands at the detector array is more than 90% of an optical power of the spectral band before the separating element. 9. The optical device according to any one of items 1 to 8, wherein a spectral component is split at or near a boundary between a first spectral band of the plurality of spectral bands and a second spectral band of the plurality of spectral bands such that a first portion of the spectral component is in the first spectral band and a second portion of the spectral component is in the second spectral band, wherein a sum of a power of the first portion and a power of the second portion is a total power of the spectral component. 10. The optical device according to any one of items 1 to 9, wherein the separating element comprises a plurality of thin-film interference filters, each associated with or associated with a different spectral band of the plurality of spectral bands. 11. The optical device according to any one of items 1 to 10, wherein the separating element comprises a diffraction grating. 12. The optical device according to any one of items 1 to 11, wherein the plurality of dispersive regions are stacked along the band separation direction. 13. The optical device according to any one of items 1 to 12, wherein a given or predetermined dispersive region of the plurality of dispersive regions disperses a spectral band of the plurality of spectral bands incident thereon, independently of dispersion by other dispersive regions of the plurality of dispersive regions. 14. Optical device according to one of items 1 to 13, wherein the optical element is designed to manipulate the dispersed spectral band such that a size of the dispersed spectral band along the dispersion direction corresponds to a size of the detector area along the dispersion direction. 15. Optical device according to one of items 1 to 14, wherein the optical element is configured to manipulate the dispersed spectral band such that a size of the dispersed spectral band along the band separation direction corresponds to a size of the detector area along the band separation direction. 16. The optical device according to any one of items 1 to 15, wherein the plurality of optical elements are configured to manipulate the dispersed spectral bands such that images of the spectral bands are stacked along the band separation direction in a plane of the detector array. 17. Optical device according to one of items 1 to 16, wherein the plurality of optical elements is configured to provide a spatial rearrangement of the plurality of spectral bands on a plane of the detector array. 18. The optical device according to any one of items 1 to 17, wherein the detector array comprises a plurality of detector areas stacked along the band separation direction. 19. Optical device according to any one of items 1 to 18, wherein the detector array comprises one or more one-dimensional (1D) detector arrays. 20. Optical device according to any one of items 1 to 19, wherein the detector array is a two-dimensional (2D) array. 21. Optical device according to one of items 1 to 20, wherein the detector array is a single-photon avalanche diode array (SPAD). 22. Optical device according to any one of items 1 to 21, wherein the detector array comprises an array of time-resolved photon counting detectors. 23. The optical device according to any one of items 1 to 22, wherein the detector surface comprises a plurality of detector surfaces and a size of a first detector surface of the plurality of detector surfaces differs from a size of a second detector surface of the plurality of detector surfaces. 24. The optical device according to any one of items 1 to 23, wherein the detector surface comprises a plurality of detector surfaces and a first spectral band of the plurality of spectral bands is or is imaged onto a first detector surface of the plurality of detector surfaces, a second spectral band of the plurality of spectral bands is or is imaged onto a second detector surface of the plurality of detector surfaces, wherein an optical resolution of the first spectral band matches an optical resolution of the second spectral band, a bandwidth of the first spectral band is smaller than a bandwidth of the second spectral band, and a total width and pixel size of the first detector surface in the dispersion direction matches a total width and pixel size of the second detector surface in the dispersion direction, such that the first spectral band has a higher spectral resolution than the second spectral band. 25. The optical device according to any one of items 1 to 24, wherein the detector surface comprises a plurality of detector surfaces, and a size of a first detector surface of the plurality of detector surfaces in the dispersion direction matches a size of a second detector surface of the plurality of detector surfaces in the dispersion direction, and a size of the first detector surface in the band separation direction differs from a size of the second detector surface in the band separation direction. 26. An optical device comprising: a separating element for separating an optical signal into a plurality of spectral bands having different spectral ranges and being spatially or angularly separated along a band separation direction; a plurality of optical elements, wherein one optical element of the plurality of optical elements is configured to manipulate a spectral band of the plurality of spectral bands in association with or in connection with an imaging of the spectral band onto a detector surface or region; and a detector array that encompasses the detector area. 27. The optical device according to item 26, further comprising a dispersive element including a plurality of dispersive regions, wherein a dispersive region of the plurality of dispersive regions is configured to disperse spectral components of the spectral band along a dispersion direction. 28. A method comprising: Separating, by a separating element of an optical device, an optical signal into a plurality of spectral bands each having a different spectral range and being spatially or angularly separated along a band separation direction; Dispersing, by a dispersive element of the optical device, spectral components of one spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band; and Manipulating, by an optical element of the optical device, the dispersed spectral band in association with or in conjunction with imaging the spectral band onto a detector surface or region of a detector array of the optical device. 29. The method of item 28, wherein a property of a first dispersed spectral band of the plurality of dispersed spectral bands differs from a property of a second dispersed spectral band of the plurality of dispersed spectral bands. 30. The method according to item 28 or 29, wherein at least one of a position, a size, or an orientation of a manipulated dispersed spectral band formed by manipulating the dispersed spectral band is different from a position, a size, or an orientation of a second manipulated dispersed spectral band formed by manipulating a second dispersed spectral band. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 620,080

[0001]

Claims

[1] Optical device comprising: a separating element for separating an optical signal into a plurality of spectral bands which are spatially or angularly separated along a band separation direction, wherein spectral ranges differ between each spectral band of the plurality of spectral bands; a dispersive element comprising a plurality of dispersive regions, wherein a dispersive region of the plurality of dispersive regions is configured to disperse spectral components of a spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band; a plurality of optical elements, wherein one optical element of the plurality of optical elements is configured to manipulate the dispersed spectral band in association with or in connection with imaging the spectral band onto a detector surface or region of a detector array; and the detector array that encompasses the detector area. [2] The optical device according to claim 1, wherein the band separation direction is perpendicular to the dispersion direction. [3] The optical device according to claim 1 or 2, wherein the plurality of spectral bands substantially do not overlap, and / or wherein a spectral resolution of a first spectral band of the plurality of spectral bands differs from a spectral resolution of a second spectral band of the plurality of spectral bands. [4] The optical device according to any one of claims 1 to 3, wherein a bandwidth of a first spectral band of the plurality of spectral bands differs from a bandwidth of a second spectral band of the plurality of spectral bands, and / or wherein a spectrum formed by a sum of a set of spectral bands of the plurality of spectral bands imaged on the detector array is discontinuous. [5] Optical device according to one of claims 1 to 4, wherein at least one spectral band of the plurality of spectral bands is not imaged onto any detector surface of the detector array, and / or wherein an optical power of a spectral band of the plurality of spectral bands at the detector array is more than 90% of an optical power of the spectral band in front of the separating element. [6] The optical device according to any one of claims 1 to 5, wherein a spectral component is split at or near a boundary between a first spectral band of the plurality of spectral bands and a second spectral band of the plurality of spectral bands such that a first portion of the spectral component is in the first spectral band and a second portion of the spectral component is in the second spectral band, wherein a sum of a power of the first portion and a power of the second portion is a total power of the spectral component. [7] An optical device according to any one of claims 1 to 6, wherein the separation element comprises a plurality of thin-film interference filters each associated with a different spectral band of the plurality of spectral bands, and / or wherein the separation element comprises a diffraction grating. [8] The optical device according to any one of claims 1 to 7, wherein the plurality of dispersive regions are stacked along the band separation direction, and / or wherein a given dispersive region of the plurality of dispersive regions disperses a spectral band of the plurality of spectral bands incident thereon, independently of dispersion by other dispersive regions of the plurality of dispersive regions. [9] Optical device according to one of claims 1 to 8, wherein the optical element is designed to manipulate the dispersed spectral band such that a size of the dispersed spectral band along the dispersion direction corresponds to a size of the detector area along the dispersion direction, and / or wherein the optical element is designed to manipulate the dispersed spectral band such that a size of the dispersed spectral band along the band separation direction corresponds to a size of the detector area along the band separation direction. [10] Optical device according to one of claims 1 to 9, wherein the plurality of optical elements is configured to manipulate the dispersed spectral bands such that images of the spectral bands are stacked along the band separation direction in a plane of the detector array, and / or wherein the plurality of optical elements is configured to provide a spatial rearrangement of the plurality of spectral bands on a plane of the detector array. [11] The optical device according to any one of claims 1 to 10, wherein the detector array comprises a plurality of detector areas stacked along the band separation direction, and / or wherein the detector array is a two-dimensional (2D) array. [12] Optical device according to one of claims 1 to 11, wherein the detector array comprises one or more one-dimensional (1D) detector arrays, and / or wherein the detector array is a single-photon avalanche diode array (SPAD), and / or wherein the detector array comprises an array of time-resolved photon counting detectors. [13] Optical device according to one of claims 1 to 12, wherein the detector surface comprises a plurality of detector surfaces and a size of a first detector surface of the plurality of detector surfaces differs from a size of a second detector surface of the plurality of detector surfaces, and / or wherein the detector surface comprises a plurality of detector surfaces and a first spectral band of the plurality of spectral bands is or will be imaged onto a first detector surface of the plurality of detector surfaces, a second spectral band of the plurality of spectral bands is or will be imaged onto a second detector surface of the plurality of detector surfaces, wherein an optical resolution of the first spectral band matches an optical resolution of the second spectral band, a bandwidth of the first spectral band is smaller than a bandwidth of the second spectral band, and a total width and pixel size of the first detector surface in the dispersion direction matches a total width and pixel size of the second detector surface in the dispersion direction, such that the first spectral band has a higher spectral resolution than the second spectral band, and / or wherein the detector surface comprises a plurality of detector surfaces and a size of a first detector surface of the plurality of detector surfaces in the dispersion direction matches a size of a second detector surface of the plurality of detector surfaces in the dispersion direction and a size of the first detector surface in the band separation direction differs from a size of the second detector surface in the band separation direction. [14] Optical device comprising: a separating element for separating an optical signal into a plurality of spectral bands having different spectral ranges and being spatially or angularly separated along a band separation direction; a plurality of optical elements, wherein one optical element of the plurality of optical elements is configured to manipulate a spectral band of the plurality of spectral bands in association with or in connection with an imaging of the spectral band onto a detector surface or region; and a detector array that encompasses the detector area. [15] The optical device according to claim 14, further comprising a dispersive element including a plurality of dispersive regions, wherein a dispersive region of the plurality of dispersive regions is configured to disperse spectral components of the spectral band along a dispersion direction. [16] Method comprising: Separating, by a separating element of an optical device, an optical signal into a plurality of spectral bands each having a different spectral range and being spatially or angularly separated along a band separation direction; Dispersing, by a dispersive element of the optical device, spectral components of one spectral band of the plurality of spectral bands along a dispersion direction to form a dispersed spectral band; and Manipulating, by an optical element of the optical device, the dispersed spectral band in association with or in conjunction with imaging the spectral band onto a detector surface or region of a detector array of the optical device. [17] The method of claim 16, wherein a property of a first dispersed spectral band of the plurality of dispersed spectral bands differs from a property of a second dispersed spectral band of the plurality of dispersed spectral bands. [18] The method of claim 16 or 17, wherein at least one of a position, a size, or an orientation of a manipulated dispersed spectral band formed by manipulating the dispersed spectral band differs from a position, a size, or an orientation of a second manipulated dispersed spectral band formed by manipulating a second dispersed spectral band.

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