Papers by Michael Kaschke
Wiley-VCH Verlag GmbH & Co. KGaA eBooks, Mar 7, 2014
The term "laser" was coined by Gordon Gould (1920Gould ( -2005)). It is an acronym for "Light Amp... more The term "laser" was coined by Gordon Gould (1920Gould ( -2005)). It is an acronym for "Light Amplification by Stimulated Emission of Radiation".
Advances in Optical Imaging and Photon Migration, 2022
Optical imaging through human tissue to determine interior structure and functional status has br... more Optical imaging through human tissue to determine interior structure and functional status has broad potential applications in many fields of medicine, just to name early cancer diagnosis of breast and scrotum or brain imaging. Images for medical diagnosis in these areas can be obtained using a number of existing techniques1. However, most of these techniques suffer from the fact that they are either invasive by utilizing ionizing radiation or they are implemented largely by non-portable, costly devices. Even more important, the images obtained by these methods almost exclusively reveal static, morphological information about the biological object, i.e. they give no indication about the functional status or the functional dynamics of the tissue under investigation.
Advances in Optical Imaging and Photon Migration, 1996
We present an instrument for frequency-domain light mammography (LIMA) which is currently undergo... more We present an instrument for frequency-domain light mammography (LIMA) which is currently undergoing a clinical test. This instrument uses two laser diodes (690 and 825 nm) which are intensity modulated at a frequency of 110 MHz. The optical signal is detected in a transmission geometry with the breast slightly compressed between two glass plates. Edge effects are corrected by an algorithm of data analysis which enhances the contrast of the optical mammograms. We report the initial results obtained with the LIMA system in the detection of malignant tumors in 69 patients. Out of 37 malignant tumors, 27 tumors (73%) were successfully detected, which shows the feasibility' and the significant potential of the method. The analysis of the 10 cases (27%) in which the tumors were not detected by LIMA provides us with a valuable input for further improvement of the current system.
Springer eBooks, 1996
Brustkrebs zahlt zu den durch Fruherkennung vermeidbaren Todesursachen. Dennoch sterben jahrlich ... more Brustkrebs zahlt zu den durch Fruherkennung vermeidbaren Todesursachen. Dennoch sterben jahrlich ca. 10000 Frauen in Deutschland an dieser Erkrankung. Durch Screening mittels Rontgenmammografie wird eine grose Zahl gesunder Frauen ionisierender Strahlung ausgesetzt, auserdem ist die diagnostische Wertigkeit der Rontgenmammografie bei Patienten unter 50 Jahren eingeschrankt [1]. Eine okonomische und gesundheitlich unschadliche Alternative bietet die Transillumination, die jedoch mit bisheriger Technologie eine unzureichende Sensitivitat fur kleine Tumoren aufweist [2]. Wir stellen erste klinische Ergebnisse mit einem neuen technologischen Ansatz [3] vor, der uber die Phasendetektion eines hochfrequent modulierten Lichtstrahles die storende diffuse Lichtstreuung im Gewebe [4] kompensiert.
Wiley-VCH Verlag GmbH & Co. KGaA eBooks, Mar 7, 2014
Journal of Photochemistry, 1986
Abstract The photoisomerization processes of two α,δ-di-(4-alkoxyphenyl)-fulgides 1 and 2 and the... more Abstract The photoisomerization processes of two α,δ-di-(4-alkoxyphenyl)-fulgides 1 and 2 and the radiationless deactivation processes of an α,δ-bifluorenylfulgide 3 were investigated by means of a picosecond excite-and-probe beam spectrometer. For 1 and 2 an ultrafast formation of EZ and ZZ isomers in the reaction sequence was observed for τ ≤ 5 ps. These reactions due to the rotation of the bulky molecular parts may be the fastest which have been observed up to date. Compound 3 exhibits ground state bleaching in the spectral range of the S 1 ← S 0 transition with a recovery time of 12 ps. The observed (S n , n ≥3) ← S 1 excited state absorption disappears with the same decay time. The results are discussed in terms of the photoisomerization model used previously in the case of stilbene. Because of the large degree of steric hindrance in the EE and EZ isomers of 1 and 2 and in compound 3 , the torsion about the ethylenic bonds to give perpendicular states which interact strongly and nonadiabatically with the ground state is considered to occur with a strong intramolecular driving force in the excited state, for which no activation barriers could be observed.
Journal of Molecular Structure, 1990
... 30 Hz 25 ns J-_ _0.1 1 Bs Excimerluser (XeCI, 308rxn1 _30 Synchrorimf .9 Unit 100is '1% P... more ... 30 Hz 25 ns J-_ _0.1 1 Bs Excimerluser (XeCI, 308rxn1 _30 Synchrorimf .9 Unit 100is '1% PM-Dye-Las 20 pl CL CL (Rho6/DDDCI, M 616-625 nm her uvv O 200 -350is 0.2-1mJ , 308 rmDFDFDFD ~ 5p_ilpf: 616-675nm Oin Module 2pJ K DP Compression Re_Omplificati0n ...
Chemical Physics, 1989
A picosecond excite-and-probe beam investigation on intermolecular electronic energy transfer (EE... more A picosecond excite-and-probe beam investigation on intermolecular electronic energy transfer (EET) between dye molecules in one-component systems (electronic energy migration -EM) and two-component systems (electronic energy trapping -ET) is presented and compared with existing theories for EET in restricted volumes. The experiments were carried out on a transient absorption spectrometer based on synchronously pumped dye laser (pulse duration 5 ps). Donor excitation density was less than 1%. In the case of ET good agreement has been obtained with the Fijrster theory, in which in addition an inhomogeneous spatial distribution of the dye molecules has been considered (part I of this study). In the case of EM direct evidence for the theory of Ediger and Fayer has been obtained by measuring the polarization anisotropy at early times after excitation.
Advances in Optical Imaging and Photon Migration
We present an instrument for frequency-domain light mammography (LIMA) which is currently undergo... more We present an instrument for frequency-domain light mammography (LIMA) which is currently undergoing a clinical test. This instrument uses two laser diodes (690 and 825 nm) which are intensity modulated at a frequency of 110 MHz. The optical signal is detected in a transmission geometry with the breast slightly compressed between two glass plates. Edge effects are corrected by an algorithm of data analysis which enhances the contrast of the optical mammograms. We report the initial results obtained with the LIMA system in the detection of malignant tumors in 69 patients. Out of 37 malignant tumors, 27 tumors (73%) were successfully detected, which shows the feasibility' and the significant potential of the method. The analysis of the 10 cases (27%) in which the tumors were not detected by LIMA provides us with a valuable input for further improvement of the current system.
Laser Chemistry, 1988
A summary of the main energy transfer (ET) mechanisms between isolated pairs of molecules in solu... more A summary of the main energy transfer (ET) mechanisms between isolated pairs of molecules in solution is presented. Various ET models for many-molecules systems are discussed in their basic assumptions and their range of applicability. Time-resolved studies of ET in solution allow to determine the predominant ET mechanism and to test ET models.
IFMBE Proceedings
Based on the principles of OCT technology which were patented in the early 1990’s in the US, Carl... more Based on the principles of OCT technology which were patented in the early 1990’s in the US, Carl Zeiss developed the first commercial generation OCT as a laboratory instrument in 1995. The inventors at MIT chose Carl Zeiss to license the product and to become their industrial development partner. During its first clinical years the instrument was still very much a lab tool used only in high-end clinics by academically interested retina specialists and major research institutions. However, the value of OCT images for clinical diagnosis became quickly accepted.
Optical Devices in Ophthalmology and Optometry, 2014
Optical Devices in Ophthalmology and Optometry, 2014
Optical Devices in Ophthalmology and Optometry, 2014
Optical Devices in Ophthalmology and Optometry, 2014
Optical Devices in Ophthalmology and Optometry, 2014
Optical Devices in Ophthalmology and Optometry, 2014
The term "laser" was coined by Gordon Gould (1920-2005). It is an acronym for "Light Amplificatio... more The term "laser" was coined by Gordon Gould (1920-2005). It is an acronym for "Light Amplification by Stimulated Emission of Radiation".
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Papers by Michael Kaschke