AU2015202843A1 - Optical slicer for improving the spectral resolution of a dispersive spectrograph - Google Patents

Abstract

An optical slicer for generating an output spot comprising an image compressor which receives a substantially collimated input beam and compresses the beam, wherein the input beam, if passed through a focusing lens, produces an input spot; an image reformatter which receives the compressed beam to reformat the beam into a plurality of sliced portions of the compressed beam and vertically stacks the portions substantially parallel to each other; and an image expander which expands the reformatted beam to produce a collimated output beam which, if passed through the focusing lens, produces the output spot that is expanded in a first dimension and compressed in a second dimension relative to the input spot. XVO 2W~ 1!93$~15 PCIY(7;42OIQIOO 1696 in ''1 >" 1 'N N 'N, s r rt ~0) N ,,,-" N N:. .. ~ 'N,, rQ f ""N a. Ins 'K N t 00 '1 r

Description

WO 25w11=5w 5 PCUTCA201 /O) 1606 OPTICAL SLICER FOR IMPROVING THE SPECTRAL RESI SOLUTIONN OF A DISPERSIVE SPEICTROGRAPH RELATED APPLICATIONS [0001] This applicaon claims priority from United States Provisional Application No, 61/245 ,762 fIed October 1, 2009 and United States Provisional Application No ,61/350,264 fl5ed June , 2010. the conterts of each of which are herein incorporated by reference: F11 LD OF INVENTION [0002] This invention rates to the field of spectroscopy and more specifically relates to improved apparatus and methods for improving spectral resolution RACKGRO UN ) [m003 A typical optical spectrograph includes a small input aperture typically a slit. however can alternatively be a circular pinhole or an optical fiber; however, for the sake of brevity will hereinafter he referred to as a slit, A converging cone of light, is proiected towards the slit and a portion of the light passes through the sli. in a typical optical spectrograph, this slit of light is projected onto a lens which collimates the slit oflight to form a beam. of parallel light rays, In a typical optcal spectrograph, a dspersive element, such as ,a prism, a transmission grating, or reflection grating, bends the collimated beams by differing amounts depending on the wavelength of the light, Typically, a camera lens brings these bent collimated beams into focus onto an array detector, such as, a charged-coupled device (CCD)detector located at the final foal planand which may record the light intensities of he various wavelengths {=14} in a typical optical spectrograph, the colliiang lens and the camera lens act as an image relay, to create images of the light passing through the slit on the detector, such as a WO 2 11/031515 PCT/CA2010/0f696 CC) detector, which may be displaced laterally depending on the wavelength of the light The resohiuion of an optical spectrograph, ise, its ability to detect and measure narrow spectral features such as absorption or emission lines, can be dependent upon various characteristics. Such characteristics may include the dispersing element, such as, the prism, transmission grating, or reflection grating; the fbeal length of the camera lens and the width of the slit For a particular dispersed and camera lens the resolution of the spectrograph can be increased by narrowing the width of the input sit, which causes each image of the light passing through the slit (depending on the wavelength of the light) and onto a detector, subtending a smaller section of the detector, allowing adjacent spectra elements to be more easil distinguished frm each other. { I0 By narrowing the width of the input slit, less light passes therethrugh which can reduce the quality of any measurements due to a reduction in the signaLto-noise ratio, In some applications such as astronomical spectroscopy, high-speed biomedical spectroscopy high resolution spectroscopy, or Raman spectroscopy. this loss of effciency can bealimiting factor in the performance ofteoptical spectrograph A device which increases the amount of 1ght that can pass through the slit by horizontally compressing and vertically expanding a spot image of an input beam of light, producing a shi while substantially maintainngight intensity or flux density. would be advantageous in the field of optical spectrography, [00061 A person of skill wiii understand that the terms horizontal, vertical and other such terms used throughout this description, such as, above and below, are used for the sake of explairag various nb'dineis of the inventon,and that such terns are not intended to be limiting of the present invention.

WO 21111/03"1-15 PCT/CA2010/f696 [000I} Optical sheers can be useful to receive an input beam and produce output beams for generating slits. The use of transparent prisms and plates to sliceian put beam can produce a slit that is tilted along the optical axis and additionally the slicing of an optical bean can occur along the hypotentuse of a 45' prism, which can result in focal point degradation due to different sections of the sliced image being located at different focal positions. The performance of such sicers can depend on the absorption coefficient and index of refraction of the prison usd (both wavelength dependent. These defieences can limit the use of such slicers as broadband devices, 100081 Other slicers, such as pupil slicers, possess drawbacks such as the inability to obtain highvresoluuion spectral information from different portions of an image Additionally, such slicers can be large in sizeand can reult in reduced or inefficient implementation with a variety of systems. Current slicers that employ a glasslased design tend to use a Lagrange constant transformer to bring light from a Ranu optical source to an optical spectrometer, The transformer nose yndical and spherical lenses, as welas two stacks of ten precisey positioned cyindcal lenses. The resulting device can haveaength of nmore han 58 inches along the main optical axis, a size at which it tends to be both difficult to maintain alignment, and difhcnh to maneuver or employ in any setting outside of a tightly-controled laboratory, 100091 in some pup slicers, two slit images can be generated on different portions of a CCD detector, This implementation can present the disadvantage that the slit images are spaced on the detector with gaps in between which can add noise to the signal, decreasing the quality of the ouiput data Additionally, in such slicers. the gaps can waste. valuable detector area, limping the number of spectra (or spectral orders) that can be fit upon the detector. Further, when using WO 20 11031515 PCT/CA201 0/0f 6 such siers, the detector readout may not be optimal due to The spectrum being spread over the detector area. [00101 Slicers using optical fiber bundles to allow the extended(often rund) image of an input souce to be formed into narrow slit can cause the degradation of the output ratio to be large and the total performance to be inefftient Existing slicer devices unitbrmly suffr this decreased efficiency and output ratio, representing a clearly-defined objective of slicer design and implementation SUMMARY OF THE INVENTION [00111 in an aspect of the present invention there is provded an optical slicer for generating an output spot comprising an image compressor which receives a substantially coated input beam and compresses the beam, wherein the input beam, if passed through a. focusing lens, produces an input spot; an image reformatter which receives the compressed beam to reformat the beam into a plurality of sliced portions of the compressed beam and vertically stacks the portions substantially parallel to each other; and an image expander which expands the refornatted beam i produce a collimated output beam which, if passed through the housing ens produces an output spot that is expanded in a first dimension, and compressed in a second cirncnsiol, relative to the input spot, 100121 In some embodiments of the present invention, the compressed beanmmay be compressed vertically and be substantially similar horizontally relative to the input beam and the output bean; nmay be expanded horizontally relative to the reformatted beam and may have substantially similar dimensions to the input beam, 10013] In other enbodinents, the optical slicer ma have a slicing factor n. The number of sliced porions of the compressed beam may be eqal to n and the output beam may be -4~ WO 2 11/031515 PCT/CA201V0f696 expanded vertically by the factor n and compressed horizontally by the factor n, relative to the input spot. [00141 In preferred embodiments n is a whole number 0from 2 to 64, mnr preferably from 2 to 32. Most preferably the value of n is 2 4, 8, 16 or 32. ((0 151 The compressor may have a convex lens and a concave lens, wherein the convex len neaav receiveiypz b lens may rece the input beam and may produce a converging beam, and the compressed bear may be formed by the converging beam passing through tbe collimting lens. In alternative embodiments, the image compressor may have a concave reflective surface and a convex reflective surface and the Concave reiective surface may receive the input beam and may produce a converging beam, and the compressed beam may be formed by the converging beam relecting off the concave reflective surface, [001 6] The image reformatter may have at least two reflective surfaces where one of the reflective surfaces may receive a portion the compressed beam and may reflet the portion for at least one reflection back and forth between the at least two reflective surfces, wherein each of tke sliced portions may be formed by a second portion of compressed beam passing by the at least two reflective surfaces after each of the at least one reflection, [001? The image expander may comnprise a concave lens and a convex lens, wherein the concave lens may receive the reformatted beam and may produce a diverging beam and the output beam may be produced by the diverging beam passing through the convex lens. In alternative embodiments, the image expander may conprise acomvexreective surface and a concave reflective surface, wherein the convex reflective surface may receive the reformatted. beam and may produce a diverging beam and the output beam may be formed by the diverging beam rejecting off the concave reflective surface.

WO 20 11031515 PCT/CA2010/0Ofr6 [00181 In some embodiments of the present irlentionthe output spot may have a light intensity value that is substantially the sane as the light intensity of the input spot [00191 In another aspect of the present invention there is provided a method of generating an output spot comprising the steps of compressing a collimated input beam, wherein the input beam, if passed through a focusing lens, produces an inputspot;reformating the cofnpressed beam into a plurality of sliced portions substantially really lly stacked and substantially parallel to each other; and expanding the reformatted beam to produce a collimated output beam which, when passed through a tocustngens, produces the output spot that is expanded in a first dimension, and compressed in a second dimension, relative to the input spot [00201 In soni embodiments, the compressed beam may be compressed vertically and may be substantially siilar horizontally relative to the input beam and the output beam may be expanded horizontally relative to the refornatted beam and may have substantially similar dimensions to the input beam. [0021 in some embodiments, the number of sliced portions may be equal to a slicing. factor, a, and the output spot may be expanded vertically by the factor a and compressed horizontally by ttor n,relative to the input spot, [00221 In a further aspect of the present invention, an optical slicer having a slicing factor, ii. is presented, the optical slicer comprsing an m omipressor which receives a substntialy collimated input beam and compresses the beam, wherein the collimated beam, if passed hogh a focusing lens, produces an input spot; an image ref matter which receives the compressed beam toreformat the beam into n sliced portions of the compressed beam and vertically stacks the portions substantial parallel to each other; and an image expander which. expands the reformatted beam to produce a collimated beam which5,when. passed through the -6- WO 20 11/031515 PCT/CA2010/0f 6 focusing lens, produces an output spot compressed by the factor n in a first dimension relative to the input spot and expanded by the factor n a second dimension relative to the inputspot [00231 in another aspect ofhe present inention a nuhiplicative optical slicer comprising a brst optical slicer having a first slicing factor n, and a second optical slicer having a second slicing factor, n, the first and second optical sicers being placed in series, and the multiplicative optical slicer having a slicing factor of m x n. BRIEF DESCRIPTION OF FIGURES [00241 For a better understanding of embodiments of the system and- methods described herein and to show more clearly how they may be carried into effect, reference will be nade by way of example, to the accotnpanying drawings in which. [0025] Figure I A shows a block diagram representation of an optical slicer having a sliing factor of two; [0026 Figure 1 shows a block diagram. representation of an optical slicer having a slicing factor of four; [0027 Figure 2 shows an isometric view of an embodiment of an optical slicer having a slicing fetor of two; [0028] Figure 3 shows an isometric view of alternative embodinent of an optical slicer having a slicing factor of two; [0029) igure 4 shows an isometric view of an alternative embodiment of an optical slicer having a slicing factor of four [00301 Figure SA shows an isometricview of an alterative embodinient of an optical slicer having a slicing factor of fOur -7 WO 20 11031515 PCT/CA2010O696 [0031] Figures 51 5B ( shows isometric and plan views of embodiments of optical elements of the optical slicer of Figure 5A; [0032] Figures bI - 5i shows an isometric view ofan embodiment of a housing cover for the optical. slicer shown in Figure 5A; [00331 Figures 6. 6 show representations of alternative embodiments of compressors for use in an embodiment of an optical slicer; and [0034] Figures 7A - 7C show representations of alternative embodiments of reformatters having a slicing factor of four for use in an embodinient of an optical sIer. DETAILED DESCRI PTION [00351 I ill be appreciated that for simplicity and clarity of illustration, where considered appropriate reference numerals may be repeated among the figures to indicate corresponding or analogous elements or steps, In addition, numerous specify dtas re set torth in order to provide a thorough understanding of the embodiments described herein, However, it wiA be understood by those of ordinary skill in the art that the embodiments described herein may be practiced without these specific details, In. other instances.wellknown methods, procedures, and components have not been described in detail so as not to obscure the embodiments described herein, Furthermorethis description is not to be. considered as limiting the scope of the embodiments described herein in any way, butL rather as merely describing the implemenation of the various embodiments described herein, [0036] With reference to Figure IA, a representation of optical slicer 100 is shown, optical slicer inciding image compressor 170, image reformatter 172 and image expander 74. Optical slicer 100 receives input beam 102, as a. collimated beam which can be produced, for example by a collimating lens or a curved mirror. Input beam 102 also generates input spot 180 WO 201 1/031515 PCT/CA20100f696 when focused by a focusing lens having substantially the same focal length as the collimating !ens or curved mirror used to produce input beam 102. [{037] image compressor 170 of optical slicer 100 receives input beam .102 and outputs vertically compressed beam 114, anamorphically compressed in the vertical dimension, and having a smaller vertical dimension than and a greater horizontal. dimension than that of input bean 102 Additionally vertically compressed beam 114, if passed through a focusmg lens with the same local length as the collimating lens or curved miWror used to produce input beam 102 produces compressor spot 182. resulting inthe focusing of compressed beam 114 to project an image that is substantially similar in the horizontal dimension as compared to input spot 180. while being expanded in the vertical dimension. [0038] In some embodiments, the image proected by vertically compressed beam 114 aay have the same horizontal width as input beam 102 however, the vertical height of vertically compressed light 114 may be compressed by the slicing factor, The term "slicing factor" is used to describe the value of the horizontal compression and vertical expansion of the output spot generated by theoutput beam of an optical slicer as compared to the horizontal and vertical dimensions of the input spot generated by the input beam into the opticalicer, the output and input spots being generated when the output and input beams are each respectively focused by the same focusing lens. [0039 For example, for an optical slicer with a slicing factor of two, such as the optical slicer represented in Figure 1A, the output slicer produces output beam 156, which, if focused through a focusing lens having a focal length substantially equal to the focal length of the coimating lens or convex mirror that generated input beam 102, causes the generation of output spot 186. Focusing input beam 102 through the same focusing lens will tend to generate input -9 WO 2ul 1103155 PCT/CA21t/f0I696 spot 180. Output spo 86 having a vertical dimension that is twice that of input spot 180 and a horizontal dimension that is half that of input spot 180, Thus, the slicing factor of the optical slicer produced by this configuration is iwo 10040] In alternative embodimentsuch as the representation of optical slicer 100 shown in [lgure I Boutput spot 8 can similarly be generaed by focusing output beam 156 through a focusing lens having a focal length substantially equal to the focal length of the collimating lens or convex irror that generated input betun 102. Focusing input beam 1,02 through the same focusing lens generates input spot 180. In this embodiment, output spot 186 has a vertical dimension that is tour times that of input spot 180 and has a horizontal dimension that is % that of input spot 180, thus, the slicing Iactor of optical slicer 100 represented in Figure lB is tour [0041] Other values of the slicing factor n are possible. The output spot generated by the output beam in a substantially similar manner as discussed above may have a vertical dmension that is n times larger than the vertical dimension of the input spoi generated by the input bean and may tend to have a horizontal dimension that is n of the horizontal dimension of the input spot, [00421 Referring back to Figure 1Avertically compressed beam 114 is received by image reformatter 172 which outputs reformatied beams 136 and 138; such reformatted tomatted beams 136 and 138 being substanally vertically stacked and substantial parallel Reformatted beams 136 and 138 are sliced potions of verially comprised beam 114. In the embodiment shown. image reformatter 174 outputs two beam slices, which in this embodiment, is equal to the sling factor of optical slicer 100; however, in some embodiments; image reformatter 172 may produce a number of slices that is greater than or less than the slicing factor of optical slicer 00; 410- WO 2 11031515 PCT/CA2010/0f696 [004-31 Each of rematted beams '6 and 138 if passed through a focusirng lens having the same focal length as the ollimating lensor eurved mirror used to produce input bean 102, proves refornatter spo I 84. Reformatter spot 184 is substantialy the same dimension both horizontally and vertically, as compressor spot 182. Since reformatted beams 136 and 138 are substantially vertically stacked and substantially parallel the individual reformatter spots generated by each of reformatted beams 136 and 138, combined to form reformatter spot 184, are projected atop one another, so as to double the light intensity of reformatter spot 184 as compared to the individual reformatter spots generated frm each of beams 136 and 138 individually, [0044] While the light intensity of refrmatter spot 1 84 in the embodiment shown in Figure IA is doubles as compared to the light intensity of each individual reformatter spot generated by each reformatted beam, in other embodiments. the light intensity of reformatter spot 184. as compared to the light intensity of each individual reformatter spot generated by each reformatted beam, corrnsponds to the number of slied portions generated by image reformatter 174, For example, with reference to Figure lB, optical slicer 100 is shown having image refRmatter 172 that produces reformatted beams 136A, 1.36B 138A and I 38B5 each of the reformatted beams being substantially parallel and substantially vertically stacked. Reformatted beams 136A, 136B, 138A and 138B are slied portions of vertically compressed beamn 114 Retormatter spot 184,generated by reformatted beams 136A. 136B, 138A and 1.38B in a substantially similar manner as discussed above, has about four times the light intensity of each individual reformaiter spot generated from each reformnatted beam 136A, 136B, 138A and 138B. f004! lWith reference back to Figure 1 A, reformatted beans 136 and 138 are received by image expander 174 which expands reformatted beams 1.36 and 138 by a factor of the slicing I 1- WO 2 11031515 PCT/CA201f00 696 factor. In the embodiment shown, the refonnatted beams 136 and R38 are expanded by a factor of two, in both the horizontal andvertcal directions (nonanamorphicaily), to produce output beam 16 output beam 156 which is made up of sliced beams 158 and 160, Sliced beams 158 and 160 are expansions of reformatted beams 136 and 138. Output beam 156 has substantially similar dimensions to that of input beam 102. Projecting output beam 156 onto a lens. such lens having substantially the same focal length as the collitnating lens or curved mirror used to produce input beam 102, tocuses output beam 156 to produce output spot 186. Output spot 186 produces an image of input spot 180 that can be compressed in the horizontal direction by the slicing factor and stretched in the vertical direction by the slicing factor while maintaining a similar light intensity as input spot 180 in embodiments, such as the embodiment represented in Figure 1 A, output spot 186 can be two times larger in the vertical direction as inputspot 180 and can be compressed by two times in the horizontal direction as input spot 180. [0046 In other embodiments, such as the embodiment shown in Figure IB, refbrmatted beams 136A. 136B, 138A and 138B are received by image expander 174, whic may be an anamorphic horizontal beam expander, to produce output beam 156, made up of output slices 158A, 1581 160A and 160B, which are expansions of reftrmatted beams 136A, 136B, 138A and 138B; expanded in the horizontal direction. it some embodiments, output bean 156 has similar dimensionsas input beam 102. With respect to the embodiment represented by Figure 11, representing an optical slicer having a slicing factor of four, when output beam 156 is projected onto a lens having substantially the same focal length as the collimating lens or curved mirror used to produce input beam 102, output beam 156 is focused to produce output spot 186, Output spot 186 can be four times larger in the vertical direction as input spot 180 and can be 12- WO 20l1!/355 PCT/CA2010/15156 compressed by four times in the horizontal direction as input spot 180, while maintaining a similar light intensity as input spot 180 [00471 it wiH be understood by those skilled in the at that the r ling output beam 156 of optical slicer 100, where optical icer 100 has a slicing factor of n.en focused by a focusing lens having substantially the same focal length as the collimating lens or curved mirror used to produce input beam 102,produces an output spot that is ni times larger in the veTtical direction and comnpressed by times in the horizontal direction, as compared to the input spot generated by input beam 102 passing through the same focusing lens, while maintaining a similar light intensity as the input spot. (0048] With reference to Figure 2, optical slicer 100 is shown, including image compressor 17%. inage reformatter 172 and image expander 174. in Figure 2. opticaslicer 100 has a slicing factor of two. Input beam 102 can be a substantially collinated beam, which can be produced by a collimating lens or a curved mirror Input beam 102 generating an input spot when focused by a focusing lens having the same focal length as the coimating lens or curved mtrror used to produce input beam 102, [00491 input beam 102 is received by image compressor 170 which outputs vertically compressed beam 114. image compressor 170 has convex cylindrica lens 104 which. receives input beam 102 and outputs vertically converging heamn 10% Vertically converging beam 108 is received by concave cylindrical lens 110 which collimates vertically converging beam 108 and outputs vertically compressed beam i14. i other embodiaents, a conavelconvex lens paring can ouut Voerticaliy compressed beam 114. In such aternative embodimentslens 104 can be a concave lens and lens 108 can be a convex tens. -11- WO 20 11031515 PCT/CA201f00 696 {.0050 Additionallyverticall compressed bean 1.4, if passed through a focusing lens wilh the sane tocal length as the collimating lens or curved mirror used to product input beam 102 produces a c.ompressor spot having a substantially similar dimension ii the horizontal direction and expanded in the vertical direction by a factor of the slicing factor as compared to the input spot generated by passing input beam 102 through the same focusing lens, In the embodiment shown, the slicing factor is twowhen compared to the input spot generated by input beam 102 using the sane focusing lens. 100511 With reference to Figures 6A-6D, alternative embodiments of image compressor 170 are shown, Referring to Figure 6A image compressor 170 has cylindrical lens 602 which receives compressor input beam 600 and focuses compressor input beam 600 fbr subsequent protection onto collimating cylindrical lens 604 to produce an output beam that is compressed relative to compressor input beam 600 n the embodiment shown in Figure 6A, collimating cylindrical lens 604 is positioned beyond the focal point of cylindrical lens 602 collimating cylindrical lens 604 outputting an inverted image of compressor input beam 600 that is compressed vertically, 00521 With reference to Fiure 6B, image compressor 170 has an optical element 61.2 having first surfae 614 which focuses compressor input beam 600 in the vertical direction and second surface 616 which substantially collimates the focused beam produced by first surface 614 The beam output from optical element 612 produces an output beam compressed vertically when compared with compressor input 600. L00521 With reference to Figure 6Gimage compressor 170 has amunorphic prisms 622 and 624, oriented such that compressor input beam 600 is refracted at the output fae of each of a h6 at m. of image compressor 170 inhis ana)norphi-c prisms 622 and 624. The resultig otput beamnf cmrso 7 nti -14~- WO 2l t1031515 PCT/CA201/f0I696 Lumbodiment produces an output bearn compressed vertically when compared with compressor input beamf 600, [00541 With reference to Figure 61), image compressor 1 70 has mirrors 632 and 634, compressor input beam 600 reflecting off concave surface of mirror 634 and prolecting onto convex surface ofT mirror 632, to produce an output beam compressed vertically when.compared with compressor input beanm 600 [0055] Skilled persons will understand that obvious variants of the compressors described herein,, and obvious onentations of such compressors elements may be implemented to produce a beam that is compressed vertically as compared to compressor input beam 600, [00561 With reference back to Figure 2, ercally compressed beam 114 is received by image reformatter 172. which outputs reformatted beams 136 and 138 such reformatted beams 136 and 138 being substantially parallel and substantially vertically stacked, hnage reformatter 1.72 includes side-bv-side fiat mirrors 116 and I 18 and vertical stacked flat mirrors 128 and 130. [0057] Side-by-side flat mirrors 116 and 1 IS receive vertically beam 114, a portion of vertically compressed beam 114 being received by side-by-side fla mirror 116 and another portion of vertical 1 compressed beam 114 being received by side-by-side flat mirror 118 which slices vertically compressed beam 114 producing sliced beams 124 and 126. Sliced beams 124 and 126 are reflected from side-by-side flat mirrors 116 and I 18 onto vertically stacked mirrors 128 and 130; sliced beam 124 being reflected onto vertical stacked mirror 128 and sliced beam 126 being reflected onto vertically stacked mirror 130. [0058] Sliced beams 124 and 126 are reflected off vertically stacked mirrors 128 and 130 to produce reformatted beams 136 and 138, Reformatted beams 136 and 138 are similar to 15- WO 20 11/031515 PCT/CA20100f696 sliced beams 124 and 126 but are substantialy vertically stacked and substantially paa In some embodiments, vertically stacked mirrors 128 and 130 are Dashaped mirrors and can be optically flat and fully aluminized, or mirrOrized. to within 50 pm of heir adjacent edges; hovvever. a kiied person will understand that other reflected properties may achieve substantialiys similar results [00> If refined beams 136 and 138 are passed through a focusing lens with the same focal length as the col1imating lens or curved mirror used to produce input beam 102, a retormnatter spot is produced. In the embodiment shown, this refornatter spot has the same horizontal dimension and a vertical dimension which is four times that of the input spot formed by passing input beam 102 through the same focusing lenr vhile maintaining a similaght intensity as the input spot. [00601 With refience to gures 7A 7, alternative embodiments of image reformatter 172 are shown. Referring to Figure 7A image reformatter 172 has multiple pairs of mirrors each to receive a portion of reformatter input beam 700 and each posiioned to produce a portion of reformatted beam 720, reformatted beam 720 being made up of be am portions 720A, 720B, 720C and 720D, each beam porion being substantially parallel and substantially vertically stacked and being a sHced portion in. refonnatter input beam 700, Mirror pairs 702 and 712 can receive a first portion of reformatter input beam 700, the first portion reflecting off mirror 702 and received by mirror 71'2 mirmt 712 being aligned to produce beam portion 72s Mirror pars 704 and 714 receive a second portion of reformatter input beam 700, the second portion reflecting off mirror 704 and received by mirror 714 mirror 714 being aligned to produce beam portion 720C, Nirror pairs 706 and 716 receive a third portion of reformater input beam 700, the third portion reflecting off mirror 706 and received by mirror 716, mirror 716 being alinned 16 WO 20 11/031515 PCT/YCA2010MIOO 6 to produce beam portion 720BR Mirror pairs 708 and 71 receive a fourth portion of reformatter input beam 700, the fourth portion reflecting off mirror 708 and received mirror 718, mirror 718 being aligned to reduce beam portion 720A A skilled person will appreciate that the addition of additional mirror pairs can increase the number of beam portions of reformatted beam 720, 1'00 -. R)rma Cs

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1 O61i ReRerring to Figure 7B, image refornter 172 includes reflective surfaces ON and 732. When in use, reformatter input 700 is received by reflective surface 730 and can be iflected back and forth between reflecte surface 732, a portion of the reflected beam being reflected off rflective surface 732 and passing by reflective surface 730 to produce a beam portion of output beam 72.0 until each of beam portions 720A, 720B 72C and 720D are generated, each beam portion being substantially parallel and substantially vertically stacked relative to one another and each being a sliced portion of reformatter input 700. A skilled person wll appreciate that additional beam portions may be generated by adjusting the position of refletive surfaces 730 and 732 to produce additional reflections back and forth between reflective surfaces 730 and 732. each of the reflecdons continuing to provide for a portion of the reflected beam to pass by reflective surface 730 to form a beam portion of output beami 730, [0062J Referring to Figure 7C% image rem'aI0er 172 may be comprised of two stages, a first stage being comprised of refective surfaces 740 and 742 and a second stage being composed of defective surfaces 744 and 746 A potion of reformatter input 700 passing by reflected surface 740, producing beam portion 750B of first output beam 750, and a second portion of input beam may be reflected off reflective surface 740 onto reflective surface 742 to form beam portion 750A of first output beam 750 which tends to pass by reflective surface 740 Each of beam morons 750A and 750B being substantially parallel and substantially vertically -17- WO 20 11031515 PCT/YCA2010MIOO 6 stacked. Beam 750 may then partly be received by reflective surfae 744, a portion of beam 750 passing by refleeuve surface 744 to pronce output beais 720 and 720D, the remaining portion of beam 750 being reflected off reflective surfaee 744 onto reflective surface 746. The reflection of the bean portion off reflective surface 746 producing output beam portions 720A and 72OB of output bean 720, which can pass by reflective surface 744, Beam portions 720A, 720B, 720(C and 720D being substantially vertically stacked and substantially parallel and being siced portions of reformnatter input 700 A skilled person will appreciate that by adding additional stages output bean; can be made up additional beam portions For example, adding an additional stage may produce eight beam portions, and a furtherstage producing, seen beamn portions. 100631 Referring back to Figure 2. reformatted beams 136 and 138 are received by image expander 174 producing output beam 156, output beam 156 being made up of sliced beams 158 and 160 Image expander 174 has concave lens 142 which can receive reformatted beams 136 and 138, and can uniformly expand refornatted beams 136 and 138 producing expanding beam 146, ane expander 1.74 can additionally have colimating lens 148 which receives expanding beam 146 and substantially collinmates expanding bean; 146, producing output beam 156. In some embodiments, concave lens 142 and collimatingi ens 148 may be cylindrical lenses wiich can expand reformated beams 1.36 and 13$ horizontally, whie maintaining their vertical dimension. 10 A 4' outputbean; 156 through a focu iin lv [0064i Pasing, output bem16truhafcsing lens having substantially the same focal length as the collimating lens or curved mirror used to produce input beam 102, focuses output beam 156 to produce an output spot. This output spot can project an image of the input spot generated by passing input bean; 102 through the same focusing lens, the output spot being .is-~ WO 2011/034515 PCT/CA20/f31566 compressed in the horizontal direction by the sicing factor and expanded in the vertical direction by the slicing factor, while maintaining a light intensity that is similar to the light intensity of the input spot generated by input beam 102 passing through the same focusing lens. In the embodiment of optical slicer 100 shown in Figure 25 the output spot generated by output beam 156 is two times larger in the vertical direction and compressed by two times in the horizontal direction, cornpared to the input spot generated by passing input beam 102 through the same focusing lens 0065 With reference to Figures 6A - 61). a skilled person would appreciate that the various alternative embodiments of the compressor shown in FHiures 6A - 61) can he used as expanders as well, if such embodiments are implemented with the light beams being projected in the opposite direction as the light beams shown in Figures 6A -6D Additionally, skilled persons wi appreciate that other apparatus comprising of optical elements can be implemented and positioned appropriately to produce expanded beam 156, [0066] With reference to Figure 3, an enbodiment of optical slicer 100 is shown. Optical slicer 100 having image compressor 170, image reformatter 1 72 and image expander 1,74, in the embodiment shown in Figure 3, optical slicer hasa slicing factor of two a compressor 170, having converging lens 302, reflective surfaces 304 and 306 and collimating ens 310:receives an inpt beam at converyng lens 302, producing a converging, beam being received and reflected hy refletive surface 304 to reflective surface 306 Theonverging beam reflecting off reflective surface 306 where it passes through collimating lens 3 10, substantially coiimating the beam, and directing the collimated beam to image refbrnatter 1,72 [00671 hage reformatter has reflective surfaces 312 and 316 each oftreflective surfaces 312 and 316 being connected to mounting brackets 314 and 318 respectively, for securement to 1 - WO 20 11/031515 PCT/CA2010/0f696 housing 320 of optical slicer 100 Reflective surfaces 312 and 316 can be D-shaped mirrors and reflective srface 312 can be oriented vertically, with the fat edge being the closest edge to the reformatted beam output by reformatter and reflective surface 316 oriented with the curved. edge facmng downwards. [0068] The compressed beam output from compressor 170 passes by refletive surface 312 and a portion of the compressed beam passes by renective surface 31 6 the remaining portion of the compressed beam relecting off reflective surface 312 back towards reflective surface 316. This first beam portion of the compressed beam passing by both reflective surfaces formng a first portion of the reformatted beam output by image reformater 172. The remaining portion of the compressed beam reflecting back towards reflective surface 31.6, and. relecting back and forth between reflective surfaces 316 and 312 each time a portion of the reflected compressed beam passing by reflective surface 312 forming a subsequent beam portion of reformatted beam. The portions of reformatted beam being substantially vertically stacked aid substantial parallel.and each representing a sliced portion of the compressed beam; [0069] Rmage reforatte 172 in the embodiment shown in Figure 3 forming a reirmatted beam made up of two beam portions, the two portions substantialy parallel and substantially vertically stacked and each representing a portion of the compressed beam output from image compressor 170. A first portion of the compressed beam reflecting off relective surface 312 and back towards reflective surface 316, this portion subsequently being reflected off refective surface 316 and passing by reflective surface 316e rsulting in the reformatted beam haWing two portions. Skilled persons will understand that an increase in the number of back and forth reflections between reflective surfaces 316 and 312 can increased the number of portions of the reformated beam, -20- WO 20 11/031515 PCT/CA201f00 696 10070] fiage expander 174, in the embodiment shown in Figure 3 receives the refonatted beam from image re1matter 172 and produces an expanded collinated output beam, the expanded colimated otput beam being of similar dimensio.ns as the input beam directed into optical slicer 100, Image expander 174, in the embodiment shown in Figure 3, can comprised of appropriate lenses and/or mirrors, to expand and collirate reformatted beam appropdiateiv. [0071] The resulting output bean when passed through a focusing lens having substantially the same focal length as the collimating lens or curved mirror that generated the collimated input bean focuses the output beam to produce an output spot, This output spot producing an image of the input spot that would be generated if the input beam were passed through the same focusing lens being compressed in the horizontal direction by the slicing actor of optical slicer 100 and expanded in the vertical direction by the siding factor of optical slicer 100,while maintaining a similar light intensity as the input spot generated by the input beam when passed through the same facussing lens. The output spot generated by the output beam of optical slicer 100 shown in Figure 3 being two times compressed in the horizontal direction and expanded by two times in the vertical direction, optical slicer 100 shown in Figure 3 being an optical slicer having a slicing factor of two. [072] With reference to Figure 4, optical slicer 100 is shown having inage compressor 170U image reformatter 172 and image expander 174, in the embodiment shown in Figure 4, optical slicer100 has a slicing factor of four. Input beam 102 can be substantially collimated, which. can he produced by a collimating lens or a curved mirror, Al- WO 20 11/031515 PCT/CA201f00 696 [0073] input beam 102 is received by image comprssor 170 can output compressed beam 452. Image compressor 170 having cylindrical concave mirror 402 which reflects input beam 102 to generate vertical converging beam 450. [0074] With additional reference to Figure SA and 5B, cylindrical concave miror 402 can be mounted to mounting bracket 502 for seurernent to base plate 480 of optical slicer 100, In some embodiments. cyl incirical concave mirror 402 may have a focal legth of 103360 mm and can be positioned at a 7.3 degree tilt horizontally and a 00 degree tilt vertically relative to the path of the incoming beam however skd led persons will understand that other focal lengths and positioning can be used to produce vertically converging beam 450, [0075] Verticaly converging beam 450 may be received by cylindrical convex mirror 404 which collimates vertically converging beam 450 outputting compressed beam 452. With additional reference to Fgures 5A and SC, cylindrical convex mirror 404 can be mounted to mounting bracket 504 for securement to base plate 480 of optical slicer 100, in some embodiments cylindrcal convex mirror 404 can have a focal length of -2584 mm and ny be positioned at a 73 degree ti horizontaly and a 0.0 degree tilt vertically relative to the path of the incoming beam; however, skilled persons will understand that other focal lengths and positioning can be used to produce compressed beam 452, [0076] In some embodiments compressed beam 452 if passed through a focusing lens wi th the same focal length as the collinating lens or curved mirror used to produce input beam 102, produces a compressor spot that is expanded in the vertical direction by the slicing factor and having a similar horizontal dimension when compared to the input spot generated by passing input source 102 through the same fiousing lens. .22- WO 2ol 11031515 PCT/CA20100If696 V3077] With reference hack to Figure 4, onpressed beam 452 is received by image reformatter 172 which outputs reformatted beam 456, refornatted beam 456 being made up of portions 45A 456B, 456(3 and 456D each being substanially parallel and substantially vertically stacked., and eacli being a sliced portion of compressed beam 452. [00781 With additional reference to Figures 5A, 5D and 5E image reformatter 12 can have Dshaped mirrors 406 and 4 10, D-shaped mirror 406 can be mounted to mounting bracket 40% and can be secured to bracket 420. bracket 420 secured to base plate 480 of optical slicer 100. Shaped mirror 406 can be vertically oriented with the fIat edge being located closest to reformatted beam 456 when in use. D-shaped mirror 406 can be positioned at a 2.5 degree tilt horizontally and a 23 degree tilt vertically downwards relative to the incoming path of compressed beam 452, when compressed beam 452 first approaches D-shaped mirror 406, [00791 D-shaped mirror 410 can be mounted to mounting bracket 412. which can be secured to bracket 422, bracket 422 being secured to base plate 480 of optical slicer 100. D shaped nrror 410 can be oriented horizontally wihthe flat edge being located closest to refornated beam 456 when in use. D1)-shaped mirror 410 can be positioned at a 25 degree tilt horizontally and a 27 degree tilt vertically upwards relative to the incoming path of compressed beam 452, when compressed beam 452 first approaches-shaped mirror 406. In some embodiments, D-shaped mirrors 406 and 410 may be Thriabs" #4BBD14&)1 -2mirrors. Skilled persons wil understand that differently shaped mirrors or other reflective surfaces, including convex or concave shaped surfaces can be used to produce refbrnatted bean 456, and additionally, alternative positioning of mirrors or other reflective surfaces may be implements to achieve substantially similar results. -23- WO 20 11031515 PCT/CA201f00 696 8Wen iuse compressed besm 4 pass over Dshaped mirror 410 and can reach the position of shaped mirror 406, In some embodiments, potion 456A of compressed beam 452 passes by D-shaped mirror 406, while the remaining portion of compressed beam 452 is reflected back and forth between D-shaped mirror 406 and D-shaped mirror 410 until reformatted beam 456, made up of portions 456A, 456B 456C and 4561) is generated. With each reKetion back and forth a portion of the rejected beam passes by D-shaped mirrOr 406 to produce a corresponding portion of reformatted beam 456. For exampleafter portion 456A. has passed by D-shaped mirror 406. the remaing portion of comnpressed beam 452 is refleted off Dshaped mirror 406, generating a first rejected beam directed toward at D-shaped mirror 410, V(081 ] D-shaped mirror 410 reflects the first reflected bean back towards D-shaped mirror 406, a portion oR this reflection passing by 3-shaped mirror 406, generating portion 456B8 the reminIg portion of this rejection be directed back at D-shaped mirror 4 10. Portion 456B being position~edbelowportioni456Aand being substantially paralel to potion 456A and substantialy vertically stacked. [00821 The remaining potion of the refecton directed at 3-shaped mirror 406., generating a subsequent reflected portion, directed back to D-shaped mirror 410. This subsequent reflected portion contacting D-shaped mirror 410 at a position below the contact position of the first reflected porno This subsequent reflected portion reflecting off D-shaped. mirror 410 back towards D-shaped mirror 400, a portionopassing by D-shaped mirror 406, generatng ponon 456C the remaining porion of te beam contacting U-sb aped miror 406. Portion 456t being positioned below portion 456B, each of portions 456A, 456B and 4560C being substantially parallel and substantially vertically stacked -24- WO 20 11/031515 PCT/CA2010/0f66 [0083] Again the remaining portion of the rejection is directed at D-shaped mirror 406, generating a. further reflected portion, directed back to D-shaped mirror 410, This further reflected portion contacts l-shaped mirror 410 at a position below the contact position of the previous reflected portion This further reflected portion reflects off D-shaped mirror 410 and passes by D-shaped mirror 406, generating portion 456D), Portion 4561) is positioned below portion 456C. each of portions 456A, 456B. 456C and 456D being substantially parallel and substantially vertically stacked and each being a sliced portion of compressed beam 452, [00841 While the embodiment shown in Figure 4 is an optical slicer that generates four beam portions a person of skill vi i understand that an increase in the number of back and fbrth reflections betweenIDshaped mirrors 406 and 410 can increased the number of portions of retornatted bean; 456. Skided persons will appreciate that the focal lengths and sizes oftmirrors 402, 404, 414 and 416 may be adjusted appropriately to accommodate such modifi-cations [0035] Referring back to Figure 4, if reformatted beam 456 is passed through a focusing lens with the sanme fical length as the cosialirting lens or curved mirror used to produce input beam 102,arefrnutter spot is produced. The produced reforimatter spot producing an image of input hear 102 that is expanded in the vertical dimension 1 the sicing factor and ha a similar horizontal dimension as compared to the input spot generated by passing input bean 102 through the same focusing lens, while maintaining a simi lair light intensity as the input spot, [0086] Retormatting beam 456 inay be received by image expander 174,producing output beam 156 .age expander 174 having cyindrical convex mirror 414 and cylindrical concave mirror 416. Cylindrical convex mirror 414 receiving and refleciing reformatted beam 456 producing horizontally divering reformatted beam 458 directed at cylindrical concave mirror 416. Cylindrical concave mirror 416 receiving horizontally diverging reforatted beam -25- WO 20 11/031515 PCT/CA201f00 696 458 and substantially collimating horizontally diverging reformatted beam 458, producing output beam 156. With additional reference to Figure 5A output beam 156 passes through output aperture 520, which can belocated beow cyindrical convexnittor 414 and through mounting bracket 514, [0087] The resulting output beam 156, if passed through a focusing lens having substantially the same focal length as the collimating lens or curved mirror that generated the input bean 102. focuses output beam 156 to produce an output spot. This output spot producing an image of the input spot that would be generated if input beam 102 is passed through the same focusing lens but being compressed in the horizontal direction by the slicing factor of optical slicer 100 and expanded in the vertical direction by the slicing factor of optical slicer 100, while maintaining a similar light intensity as the input spot, [00881 With additional reference to Figures 5A. and .cylindrical convex mirror 414 can be secured to mounting bracket 514 for securenent to base plate 480 of optical slieer 100 In some embodiments, mounting bracket 514 can have output aperture 520 oated tr ough where in some embodiments output aperture 520 can belocated below the position of cylindrical convex mirror 414 when secured to mounting bracket 514. In some embodiments, cylindrical convex nirmro 414 may have a focal. lgth of -25.84 n and may be positioned at a 0.0 degree tilt horizontally and a 63 degree tilt verticaly downwards relative to the path of the incoming beanm ho wever skilled persons will understand that other focal lengths and positioning can be used to produce horizontally diverging reformatted beam 458 {00091 With additional reference to Figures 5A and 5G cylindrical concave mirror 416 can be mounted to mounting bracket 5 16 for securement to base Aate 480 of opticalslicer 100. In some ebodiments, base plate 480 having an inden therein which can receive a portion of -2 6- WO 2 11/031515 PCT/YCA2010/0f 6 mounting bracket 516 to provide that a portion of concave mirror 416 can rest below a top surface of base plate 480; in some embodiments, cylindrical concave mirror 416 can have a focal length of 103,360 mm and can be positioned at a 0,, degree tilt horizontally and a 63 degree tih vertically upwards relative to the path of the.in.mig.eam; however skilled p will understand that other focal lengths and positioning can be used to produce output beam 156. [0090 With reference to Figure 5 optical slicer 100 can be covered by housing cover 486 secured to base plate 480 to protect the interior elements of optical. shicer 100, for example from dust and other partculates housing cover 486 can have input aperture 482 for receiving the input beam and can addiionally have output aperture 484 for outputting the output beam fon optialslicer 100, [0091] In sone embodiments of the optical slicer described herein, a second. optical slicer may be placed in series wherein outpt bean 156 from a first optical slicer may be input beam 102 into a second optical slier in such emribodimnents it has been found that the slicing factor may be multiplicative; for example combining two slicers having a slicing factor of four in series may tend to result in an overall slicing fiator of sixteen. [00921 While the present invention can be used with any device that tends to use light as an input, one example of the use of the optical slicer described herein may be in the field of speetroscopy. A. general. spectrometer is a device that disperses light such that the intensity value of light as a function ofwavelength can be recorded on a detector. For readings that require a higher spectral resolution, a narrower slit is needed in a direct relationship to spectral resolution and typically narrow slit, will provide a reduction in the light intensity received by the general spectroneter device. Positioning an optical slicer in front of the input of a genenl spectrometer device can tend to produce an input into the general spectrometer device slit aving an increased -27- WO 2 11031515 PCT/YCA201/0MIO06 light intensity value as compared to a slit without an optical slicer. by the factor of the slicing factor, over the area of the slit, tending to provide increased spectral resolution without sacrificin lht siginaL intensity. [0093] A subset of spectroscopy is interteronetric spectroscopy; the defining feature of interferometric spectrometers is that the dispersing element used is not a grating or a prism, Rather, the dispersion is achieved another way, such as by taking the Fourier transforn of the pattern generated by two interfering beams. The slicer not only increases brightness of the output, but also allowsglare improvements in the contrast of the ntrference fringes as well as signal-to-noi se ratio. [0094] An optical slicer can be used in a subset of OCT called Fourier domain OCT (FD OCT) and more specially in a specificnplementation FD-OC'1 called Spectrali Domain CC'O (SD-OCT), An S DOCT instrument is an interferometi spectrometer with a dispersive spectrometer to record the signal An optical slicer can be included at the input to the dispersive spectmeter righn before the dispersive beam element in a collimated beam path. [0095] i A further subset of interferometric spectrometry as pertains to, medical imaging is Optical Coherence Tomography (OC), a technique that uses an interferotnei spectrometer to make an image. A slicer will improve the throughput, as well as the fringe contrast, of the OCT device; the result is that the slicer can improve the depth penetration possible with OCT systems, speeding imaging time and increasing the value of the captured image. An optical slicer can be included at the input to the OCT device, [00961 A father application of the slicer is in the field of miniature spectroscopy, particularly as it pertains to Ranman spectroscopy Current Raman spectrometers have been implemented that are miniaturized to handheld scale, As the slicer can be used to increase -28- WO 20 11031515 PCT/CA201001696 hroughput in any systems whereilight is used as the input source, a miniaturized embodiment of the slicer can be used in cenjunctin with miniaturized spectrometers, like the Raimu to increase spectral resolutionincrease output signal strength, and decrease scan tine. An optical slicer can be incIded at the input to the: Raman spectroscopy device [0097] The present invention has been described Ih regard to specific embodiments. However, it will be obvious to persons skilled in the art that a number of variants and modifications can be made without departing from the scope of the invention as described herein.

Claims (25)

1. A beam reformatter comprising optical elements configured to receive a beam and to split the beam according to the spatial position of the light within the beam into a plurality of sliced beam portions, the optical elements further configured to distribute and propagate two or more of the plurality of sliced beam portions in substantially the same direction to create a reformatted composite beam, wherein the plurality of sliced beam portions each contain the same spectral information as the received beam.

2. The beam reformatter of claim 1, wherein the optical elements comprise one or more pairs of reflective surfaces.

3. The beam reformatter of claim 2, wherein the optical elements are configured so that at least one of the plurality of sliced beam portions is formed from a portion of the received beam passing by the one or more pairs of reflective surfaces without reflection.

4. An optical slicer that receives a beam and configures the beam for generating an output spot from the configured beam, comprising: a beam reformatter comprising optical elements to receive a beam and to split the beam into a plurality of beam portions, the optical elements further configured to distribute and propagate two or more of the plurality of beam portions in substantially the same direction to create a reformatted composite beam; and at least one of - 30 - a beam compressor comprising optical elements configured to receive the beam and compress the beam; and a beam expander comprising optical elements configured to receive the beam and expand the beam, wherein the plurality of beam portions each contain the same spectral information as the received beam; and wherein the output spot has different dimensions relative to a spot produced in the same manner from the beam received by the optical slicer.

5. The optical slicer of claim 4, wherein the at least one of a beam compressor and a beam expander comprises a beam expander, the beam expander receiving the reformatted beam from the beam reformatter and expanding the beam to produce the configured beam for producing the output spot with different dimensions relative to a spot produced in the same manner from the beam received by the optical slicer.

6. The optical slicer of claim 4, wherein the at least one of a beam compressor and a beam expander comprises both a beam compressor and a beam expander, the beam compressor receiving the beam and compressing the beam and passing the compressed beam to the beam reformatter, and the beam expander receiving the reformatted beam from the beam reformatter and expanding the beam to produce the configured beam for producing the output spot, wherein the output spot is expanded in a first dimension and compressed in a second dimension relative to a spot produced in the same manner from the beam received by the optical slicer. - 31 -

7. The optical slicer of claim 4, wherein the optical elements of the beam reformatter comprise at least one pair of reflective surfaces.

8. The optical slicer of claim 4, wherein the optical elements comprise at least one of a segmented mirror, a flat non-mirror surface coated with a reflective substance, a refractive element, a prism, a Fresnel lens, a toroidal mirror or lens, a cylindrical mirror or lens, and a diffraction grating.

9. The optical slicer of claim 4, wherein the configured beam has substantially dissimilar dimensions relative to the beam received by the optical slicer.

10. The optical slicer of claim 4, wherein the configured beam has substantially similar dimensions relative to the beam received by the optical slicer.

11. The optical slicer of claim 4, wherein the configured beam is expanded in a first dimension and compressed in a second dimension relative to the beam received by the optical slicer.

12. The optical slicer of claim 4, wherein the beam compressor comprises a convex lens and a concave lens, wherein the convex lens receives the beam and produces a converging beam and the beam is compressed by the converging beam passing through the concave lens.

13. The optical slicer of claim 4, wherein the beam compressor comprises a concave reflective surface and a convex reflective surface, wherein the concave reflective surface receives the beam and produces a converging beam and the beam is compressed by the converging beam reflecting off the convex reflective surface. - 32 -

14. The optical slicer of claim 4, wherein the optical elements are configured to alter the dimensions of the beam differently along a first dimension relative to a second dimension.

15. The optical slicer of claim 4, wherein the beam expander comprises a concave lens and a convex lens, and wherein the concave lens receives the beam and produces a diverging beam and the expanded beam is produced by the diverging beam passing through the convex lens.

16. The optical slicer of claim 4, wherein the optical elements have different focal lengths along different axes of the same optical element.

17. The optical slicer of claim 4 wherein the beam expander comprises a convex reflective surface and a concave reflective surface, and wherein the convex reflective surface receives the beam and produces a diverging beam and the expanded beam is formed by the diverging beam reflecting off the concave reflective surface.

18. The optical slicer of claim 4, wherein the at least one of a beam compressor and a beam expander compresses or expands, respectively, the beam along only one axis of the beam.

19. The optical slicer of claim 4, wherein the configured beam has a light intensity substantially the same as the light intensity of the beam received by the optical slicer.

20. The optical slicer of claim 4, wherein the beam received by the optical slicer or the configured beam is at least one of a collimated, diverging or converging beam. - 33 -

21. A spectrometer comprising the optical slicer of claim 4, wherein the slicer is positioned upstream of the optical input slit of the spectrometer to direct the output spot therethrough.

22. A method of configuring a beam for generating an output spot from the configured beam, comprising: receiving a beam and splitting the beam into a plurality of beam portions; distributing and propagating two or more of the plurality of beam portions in substantially the same direction to create a reformatted composite beam; and at least one of compressing the beam and expanding the beam, wherein the plurality of beam portions each contain the same spectral information as the received beam, and the output spot produced from the configured beam has different dimensions relative to a spot produced in the same manner from the beam prior to configuration.

23. The method of claim 22, wherein the configured beam has substantially dissimilar dimensions relative to the beam prior to configuration.

24. A method of reformatting a beam received at a beam reformatter, comprising splitting the beam according to the spatial position of the light within the beam into a plurality of sliced beam portions, and distributing and propagating two or more of the plurality of sliced beam portions in substantially the same direction to create a reformatted composite beam, - 34 - wherein the plurality of sliced beam portions each contain the same spectral information as the received beam.

25. The method of claim 24, wherein optical elements are used to distribute and propagate the sliced beam portions, and at least one of the plurality of sliced beam portions is formed from a portion of the received beam passing by the optical elements without being repositioned. - 35 - -36-