Trees are among the natural resources that are becoming less abundant and more costly. The trend to utilize as much as possible of each harvested tree is well established and will continue for both economic and ecological reasons. This paper considers an automated system designed to increase the percentage of useful lumber (the yield) obtained from millwork grades of softwood.
{"title":"Increasing production yields with a laser scanner lumber inspection system","authors":"P. Mueller, Raymond T. Hebert","doi":"10.1364/cleos.1976.tua6","DOIUrl":"https://doi.org/10.1364/cleos.1976.tua6","url":null,"abstract":"Trees are among the natural resources that are becoming less abundant and more costly. The trend to utilize as much as possible of each harvested tree is well established and will continue for both economic and ecological reasons. This paper considers an automated system designed to increase the percentage of useful lumber (the yield) obtained from millwork grades of softwood.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134346590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Digitally controlled ground electrooptical systems have been designed such that all possible total system uncertainties are accounted for prior to track. The definition of total system here encompasses the satellite, earth, and station as a whole measured to common references. Considerations include utilizing stabilized oscillators to generate compensated Universal Time (UTC) thus reducing system time uncertainties to less than 2 μsec, reducing pointing uncertainties to less than 1 sec of arc with 21-bit encoders and knowledge of station geodetic location to within a small number of feet. Sensor biases and errors both static and dynamic are removed or modeled prior to track. Initially this is accomplished through a precise static (moving at sidereal rates) calibration of the mount to the celestial sphere. Data on several hundred stars are resident in the computer, and where specific stars are selected the system will continually point open loop to that reference as angular deviations are measured. With sufficient observations of a sampled distribution of known stars, the modeling constants are computed and the entire process repeated until angular deviations are zero. Slew measurements are made to determine dynamic constants. The system is then used to track known satellites and over-all system performance observed to insure that modeling is correct. A generalized block diagram is shown in Fig. 1.
{"title":"Computer controlled ground electrooptical systems for deep space operations","authors":"E. P. Schelonka","doi":"10.1364/cleos.1976.tuc1","DOIUrl":"https://doi.org/10.1364/cleos.1976.tuc1","url":null,"abstract":"Digitally controlled ground electrooptical systems have been designed such that all possible total system uncertainties are accounted for prior to track. The definition of total system here encompasses the satellite, earth, and station as a whole measured to common references. Considerations include utilizing stabilized oscillators to generate compensated Universal Time (UTC) thus reducing system time uncertainties to less than 2 μsec, reducing pointing uncertainties to less than 1 sec of arc with 21-bit encoders and knowledge of station geodetic location to within a small number of feet. Sensor biases and errors both static and dynamic are removed or modeled prior to track. Initially this is accomplished through a precise static (moving at sidereal rates) calibration of the mount to the celestial sphere. Data on several hundred stars are resident in the computer, and where specific stars are selected the system will continually point open loop to that reference as angular deviations are measured. With sufficient observations of a sampled distribution of known stars, the modeling constants are computed and the entire process repeated until angular deviations are zero. Slew measurements are made to determine dynamic constants. The system is then used to track known satellites and over-all system performance observed to insure that modeling is correct. A generalized block diagram is shown in Fig. 1.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133883115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Results of recent experiments involving guided optical waves and surface acoustic waves have demonstrated that it is possible to achieve very efficient interaction with noncollinear, coplanar Bragg diffraction in LiNbO3 substrate.1 Efficient diffraction results from the fact that both the optical and the SAW are confined in one dimension and that the frequency range of the SAW may be chosen to facilitate a good matching between the confinement of the optical waves and the penetration depth of the SAW. In particular, by employing multiple surface acoustic waves (Fig. 1), deflectors with very large diffraction efficiency-bandwidth product and excellent beam quality have been realized most recently. 1 For example, the frequency response and the light beam quality of a deflector, which has a 360-MHz bandwidth,2 are shown in Figs. 2 and 3, respectively. Total electric drive power of only 200 mW was required to diffract 50% of the incident light power. This particular deflector has deflected a light beam of a 4-mm aperture into 400 resolvable spots at a random-access switching time of 1.24 μsec. The above combination of performance figures far exceeds that obtained previously. It should be possible to achieve even better performance figures by optimizing the optical waveguide and surface acoustic wave parameters.
{"title":"High-performance guided-wave acoustooptic beam deflectors","authors":"C. Tsai","doi":"10.1364/cleos.1976.wd3","DOIUrl":"https://doi.org/10.1364/cleos.1976.wd3","url":null,"abstract":"Results of recent experiments involving guided optical waves and surface acoustic waves have demonstrated that it is possible to achieve very efficient interaction with noncollinear, coplanar Bragg diffraction in LiNbO3 substrate.1 Efficient diffraction results from the fact that both the optical and the SAW are confined in one dimension and that the frequency range of the SAW may be chosen to facilitate a good matching between the confinement of the optical waves and the penetration depth of the SAW. In particular, by employing multiple surface acoustic waves (Fig. 1), deflectors with very large diffraction efficiency-bandwidth product and excellent beam quality have been realized most recently. 1 For example, the frequency response and the light beam quality of a deflector, which has a 360-MHz bandwidth,2 are shown in Figs. 2 and 3, respectively. Total electric drive power of only 200 mW was required to diffract 50% of the incident light power. This particular deflector has deflected a light beam of a 4-mm aperture into 400 resolvable spots at a random-access switching time of 1.24 μsec. The above combination of performance figures far exceeds that obtained previously. It should be possible to achieve even better performance figures by optimizing the optical waveguide and surface acoustic wave parameters.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133385137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Chen, M. Didomenico, P. W. Dorman, M. Karr, T. Rich, P. Shumate, R. Smith
A feedback-stabilized GaAIAs injection laser optical communication source for transmission of NRZ data at 44.7 Mb/sec has been built and tested. Standard ECL input levels operate the emitter-coupled driver circuitry in which the stripe geometry double-heterostructure GaAIAs laser diode (λ = 825 nm) appears as a collector load. The laser is pre-biased near threshold by a separate feedback-stabilizing circuit. This circuit, utilizing an 800-kHz operational amplifier, compares the optical output measured from the back mirror of the laser using a PIN photodiode with data-pattern reference. In this way, closed-loop control of the prebias current makes the optical output insensitive to thermal effects and component aging. The driver–feedback components are assembled on thick-film hybrid integrated circuits. The laser, indium soldered to a gold-plated copper stud, and the thick-film driver circuit are mounted on an aluminum heat sink which forms the body of the driver package. A 40-cm Teflon-sheathed connectorized section of optical fiber is brought through the aluminum housing, strain relieved, and epoxied in place after positioning near the front mirror of the laser. Efficient coupling (50% or greater) between the laser and optical fiber is achieved by melting a spherical lens on the tip of the fiber. The driver package accessed through pins connected to the thick-film circuit is completed by filling the active volume of the heat sink with casting epoxy. The feedback package is of similar design but has only electrical inputs and outputs. The two-package subsystem launches a minimum of 1-mW peak power into a fiber with a ≈0.002-in. graded-index core. The extinction ratio is typically 15:1; peak-to-peak amplitude variation in the output is ~8%. The subsystem operates from 5°C to 55°C and tolerates ±5 % variations in the +5-V and -5.2-V supplies.
{"title":"GaAIAs laser transmitter for optical fiber transmission systems","authors":"F. Chen, M. Didomenico, P. W. Dorman, M. Karr, T. Rich, P. Shumate, R. Smith","doi":"10.1364/cleos.1976.the6","DOIUrl":"https://doi.org/10.1364/cleos.1976.the6","url":null,"abstract":"A feedback-stabilized GaAIAs injection laser optical communication source for transmission of NRZ data at 44.7 Mb/sec has been built and tested. Standard ECL input levels operate the emitter-coupled driver circuitry in which the stripe geometry double-heterostructure GaAIAs laser diode (λ = 825 nm) appears as a collector load. The laser is pre-biased near threshold by a separate feedback-stabilizing circuit. This circuit, utilizing an 800-kHz operational amplifier, compares the optical output measured from the back mirror of the laser using a PIN photodiode with data-pattern reference. In this way, closed-loop control of the prebias current makes the optical output insensitive to thermal effects and component aging. The driver–feedback components are assembled on thick-film hybrid integrated circuits. The laser, indium soldered to a gold-plated copper stud, and the thick-film driver circuit are mounted on an aluminum heat sink which forms the body of the driver package. A 40-cm Teflon-sheathed connectorized section of optical fiber is brought through the aluminum housing, strain relieved, and epoxied in place after positioning near the front mirror of the laser. Efficient coupling (50% or greater) between the laser and optical fiber is achieved by melting a spherical lens on the tip of the fiber. The driver package accessed through pins connected to the thick-film circuit is completed by filling the active volume of the heat sink with casting epoxy. The feedback package is of similar design but has only electrical inputs and outputs. The two-package subsystem launches a minimum of 1-mW peak power into a fiber with a ≈0.002-in. graded-index core. The extinction ratio is typically 15:1; peak-to-peak amplitude variation in the output is ~8%. The subsystem operates from 5°C to 55°C and tolerates ±5 % variations in the +5-V and -5.2-V supplies.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116530999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Salzman, J. M. Crowell, B. J. Price, K. M. Hansen, M. Ingram, P. Mullaney
Light-scattering techniques represent an appealing approach to the flow-system analysis and sorting of mammalian cells because they do not require fixation and staining, procedures that kill the cells and can introduce artifacts. A flow-system instrument has been developed1,2 at the Los Alamos Scientific Laboratory in which the intensity of light scattered by a cell as it passes through a focused laser beam is measured simultaneously at up to 32 angles between 0° and 21° with respect to the laser beam, and the scatter pattern is transferred to a computer for analysis.
{"title":"Scattering techniques to detect and record various human cell types","authors":"G. Salzman, J. M. Crowell, B. J. Price, K. M. Hansen, M. Ingram, P. Mullaney","doi":"10.1364/cleos.1976.wh2","DOIUrl":"https://doi.org/10.1364/cleos.1976.wh2","url":null,"abstract":"Light-scattering techniques represent an appealing approach to the flow-system analysis and sorting of mammalian cells because they do not require fixation and staining, procedures that kill the cells and can introduce artifacts. A flow-system instrument has been developed1,2 at the Los Alamos Scientific Laboratory in which the intensity of light scattered by a cell as it passes through a focused laser beam is measured simultaneously at up to 32 angles between 0° and 21° with respect to the laser beam, and the scatter pattern is transferred to a computer for analysis.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115927195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In any laser fusion scheme dependent on adiabatic implosion of the fusion target, it is of the utmost importance to illuminate the target uniformly over its entire surface area. A convenient method of providing illumination over the entire spherical surface from two beams was proposed by Thomas.1 In this method, a catadioptric system is employed, involving a fast (NA 0.7) lens and a pair of ellipsoidal mirrors of eccentricity ⅓. Subsequent refinements of this scheme have been developed at the Lawrence Livermore Laboratory.2
{"title":"Design of illumination systems for two-beam laser fusion experiments","authors":"A. Glass, E. Goodwin, J. Trenholme","doi":"10.1364/cleos.1976.thd4","DOIUrl":"https://doi.org/10.1364/cleos.1976.thd4","url":null,"abstract":"In any laser fusion scheme dependent on adiabatic implosion of the fusion target, it is of the utmost importance to illuminate the target uniformly over its entire surface area. A convenient method of providing illumination over the entire spherical surface from two beams was proposed by Thomas.1 In this method, a catadioptric system is employed, involving a fast (NA 0.7) lens and a pair of ellipsoidal mirrors of eccentricity ⅓. Subsequent refinements of this scheme have been developed at the Lawrence Livermore Laboratory.2","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116150773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Methods using laser Doppler velocimeters have been developed for measuring the dynamic relaxation time (τ p ) of aerosol particles and droplets. For real-time measurement of aerodynamic size spectra in the range of 0.2-50.0 μm in diameter, the most promising methods employ (1) acoustic excitation, for the size range of 0.2-5.0 μm in diameter, and (2) gravity settling, for the size range of 5.0-50.0 μm in diameter. Both methods have been applied to rapid in situ measurement of the size distribution of stable and unstable aerosols. Experimental results indicate that these newly developed methods compliment the existing methods of real-time aerosol size analysis.
{"title":"Aerosol sizing by laser Doppler relaxation-time measurement","authors":"M. Mazumder, S. N. Nichols, R. Overbey","doi":"10.1364/cleos.1976.tuf3","DOIUrl":"https://doi.org/10.1364/cleos.1976.tuf3","url":null,"abstract":"Methods using laser Doppler velocimeters have been developed for measuring the dynamic relaxation time (τ\u0000 p\u0000 ) of aerosol particles and droplets. For real-time measurement of aerodynamic size spectra in the range of 0.2-50.0 μm in diameter, the most promising methods employ (1) acoustic excitation, for the size range of 0.2-5.0 μm in diameter, and (2) gravity settling, for the size range of 5.0-50.0 μm in diameter. Both methods have been applied to rapid in situ measurement of the size distribution of stable and unstable aerosols. Experimental results indicate that these newly developed methods compliment the existing methods of real-time aerosol size analysis.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"177 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124367163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The implications of high density focal plane arrays (>5000 detectors) upon the design and performance of next generation thermal imaging systems are discussed. The system design tradeoffs with respect to increased fields of view, improved sensitivity, and resolution are presented.
{"title":"Trends in next generation thermal imaging using integrated focal planes","authors":"Lloyd M. Candell, Paul J. Beckett","doi":"10.1364/cleos.1976.thc5","DOIUrl":"https://doi.org/10.1364/cleos.1976.thc5","url":null,"abstract":"The implications of high density focal plane arrays (>5000 detectors) upon the design and performance of next generation thermal imaging systems are discussed. The system design tradeoffs with respect to increased fields of view, improved sensitivity, and resolution are presented.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"183 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124608894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Analysis of the light scattered by individual particles passing through a focused laser beam has recently become a common technique for characterizing air pollution aerosols. Early optical particulate analyzers utilized the light scattered in a single field of view to classify particles by size, but were hampered by relatively low resolution. This was due to effects of the index of refraction on the functional dependence of the scattered intensity on particle diameters1 and to variations in incident light intensity within the sensitive volume, which is Gaussian for laser beams.
{"title":"Uncertainties in particle size distributions measured with ratio-type single particle counters","authors":"E. Hirleman, S. Wittig","doi":"10.1364/cleos.1976.tuf4","DOIUrl":"https://doi.org/10.1364/cleos.1976.tuf4","url":null,"abstract":"Analysis of the light scattered by individual particles passing through a focused laser beam has recently become a common technique for characterizing air pollution aerosols. Early optical particulate analyzers utilized the light scattered in a single field of view to classify particles by size, but were hampered by relatively low resolution. This was due to effects of the index of refraction on the functional dependence of the scattered intensity on particle diameters1 and to variations in incident light intensity within the sensitive volume, which is Gaussian for laser beams.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129505671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Large laser systems for fusion research employ disk laser amplifiers at the output of each amplifier chain owing to the superior nonlinear performance of large-aperture (d > 10-cm) disk amplifiers over rod amplifiers of the same aperture. This superior performance arises from three sources: (1) generally higher attainable gain coefficients; (2) reduction in beam intensity inside the Brewster’s angle disks; and (3) the air spaces between successive disks permitting diffraction to diverge small-scale self-focusing filaments.
{"title":"Design of disk laser amplifiers for laser fusion applications","authors":"W. Fountain, W. Hagen, G. Linford","doi":"10.1364/cleos.1976.tha5","DOIUrl":"https://doi.org/10.1364/cleos.1976.tha5","url":null,"abstract":"Large laser systems for fusion research employ disk laser amplifiers at the output of each amplifier chain owing to the superior nonlinear performance of large-aperture (d > 10-cm) disk amplifiers over rod amplifiers of the same aperture. This superior performance arises from three sources:\u0000 (1) generally higher attainable gain coefficients;\u0000 (2) reduction in beam intensity inside the Brewster’s angle disks; and\u0000 (3) the air spaces between successive disks permitting diffraction to diverge small-scale self-focusing filaments.","PeriodicalId":301658,"journal":{"name":"Conference on Laser and Electrooptical Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125824694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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