Abstract
摘要:近年來由於光學影像的快速發,加上生醫科技愈來愈受到重視,使得具備高速、高解析度的生物影像系統,成為當今各國研究的重點項目。本計劃的研究整體目標,在研發設計新型的光電生醫影像系統:「體積全像生醫影像系統(Volume Holographic Bio-Imaging System)」。此新型光電生醫影像系統,由所設計的多工體積全像術(volume holographic imaging, VHI)與泰柏效應(Talboteffect inspired, TEI)應用照明術之結合成為泰柏-體積全像術(TEI-VHI),不須耗時掃描,便可以高速、高解析度提供生物組織立體與光譜的資訊。多工體積全像術經過精確的設計,將具備角度–波長的高選擇性,透過此特殊功能的體積全像率波器(本計劃將採用PQ-PMMA製作),可同時取得生物組織的三維資訊與光譜訊息,呈現在數位相機(CCD)上。另外,與其它傳統的光學生醫系統之局限於一維點掃描(1D point scanning)或二維掃描(2Dscanning)相比較, TEI-VHI系統經由Talbot effect inspired 照明術,結合多工體積全像術VHI準確的設計,在不須掃描的機制下,同時提供三維(3D)高解析度(resolution)及光學斷層(opticalsectioning)資訊。此新型光電生醫影像系統,具備其它現有的系統所沒有的優點包括: 高光譜解析度、高三維解析度、不須掃描的高速立體影像系統。除次之外,雖然不在本此計劃的規劃,但若將此系統縮小化,將具備內視鏡發展的實力。在這個三年計畫中,將設計、研發、製作體積全像生醫影像系統,分為下列四個目標進行:目標一:發展與研製可取得立體與光譜資訊的多工體積全像術的影像系統,並適當調整系統的設計,優化系統的整體解析度。此外,還將探討體積全像顯微術的三維孔徑工程(3D pupil engineering),更有效率運用體積全像多工技術(multiplexing)。目標二:測試與量化多工體積全像術影像(VHI)系統的性能。此過程的量化參數,包括:系統取得的深度、縱向與橫向的解析度、光譜解析度。也將用已知參數的三維測試物體(well-characterized tissue phantom)來測試系統的性能。目標三:發展與研製不須掃描機制,就可取得多層三維光學斷層(optical sectioning)的泰柏效應照明–多工體積全像(TEI-VHI)影像系統,並適當調整系統的設計,優化系統的整體解析度。此外, 也將用已知參數的三維測試物體,探討非螢光(label-free)與螢光(fluorescence),更有效率運用體積全像多工技術(multiplexing)。目標四:測試與量化泰柏效應照明–多工體積全像(TEI-VHI)影像系統的性能。此過程的量化參數與目標二相同。也將用老鼠組織(in-vivo and ex-vivo mouse tissue sample)更真實地進行優化與測試系統的性能。
Abstract: The overall goal of the research is to develop, fabricate and test a new type of optical imagingsystem that requires no scanning and can rapidly extract three-dimensional (3D) information withfine optical sectioning from biological samples. The proposed system is based on multiplexedvolume holographic filters used in conjunction with conventional optical imaging components toform a Talbot-effect inspired volume holographic imaging (TEI-VHI) system.The high angular-wavelength selectivity of a VHI system can be used to simultaneously imagemultiple projections with spectral information from different depths within a 3D biological sample. Inaddition, Talbot-effect inspired (TEI) illumination can be used to significantly enhance axialselectivity at multiple depths of a 3D sample that is being observed. Multiple layer-sections of theobject are projected on the CCD image plane through a volume hologram, which consists ofmultiplexed holographic gratings as optical Bragg filters in a volume holographic recording material.For our experiments, we will use phenanthrenequinone-doped methyl methacrylate (PQ-PMMA) asthe holographic recording materials.The proposed system has many advantages over competing with other optical imaging techniquesfor biological samples. These include simultaneous high spatial and spectral image resolution withthe same optical system, and operation in high speed with non-scanning 3D informationacquisition. In addition, compared with conventional structured illuminated microscopy, the systemis capable of fine optical sectioning at multiple depths at the same time without scanning. Whilebeyond the scope of the current proposal, the system can also be combined with a commerciallyavailable miniature optical image relay systems for endoscopic operation.The specific aims of this proposal are as follows:Specific aim 1: Design and fabricate an imaging system based on volume holographic filter forspatial and spectral imaging of tissue samples. Several candidate system configurations will beexamined to optimize spatial and spectral resolution. This work will include investigating 3Dpupil engineering techniques for optimization and image multiplexing.Specific aim 2: Characterize the optimized imaging system by quantifying parameters such as thepoint-spread function, image depth, dynamic range, and spectral resolution. Experiments will beconducted on well-characterized tissue phantoms.Specific aim 3: Design and fabricate the optimized TEI-VHI system to simultaneously provide fineoptical sectioning from multiple depths without scanning. This work will include investigatingboth label-free and fluorescence imaging of well-characterized tissue phantoms.Specific aim 4: Characterize the optimized TEI-VHI system by quantifying parameters as describedin Specific aim 2. Experiments will be conducted on proof of principle imaging in ex-vivo and invivomouse tissue samples.
Keyword(s)
共軛焦顯微鏡
光學同步斷層攝影
體積全像生醫影像系統
confocal microscopy,optical coherence tomography
volume holographic bio-imaging