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Ping An - One of the best experts on this subject based on the ideXlab platform.
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Bivariate analysis of 3D structure for stereoscopic image quality assessment
Signal Processing-image Communication, 2018Co-Authors: Liquan Shen, Ping AnAbstract:Abstract Human visual system (HVS) identifies each unit of stereo-pair into binocular or monocular perception depending on distortions and depth perception. However, these HVS properties still have a large room for exploration in stereoscopic image quality assessment (SIQA) research field. In this paper, a bivariate natural scene statistics (NSS) model is proposed to capture image quality by extracting features from binocular and monocular perception regions, respectively. In the implementation details, the stereo-pair is first segmented into various regions based on spatial information of its disparity. Then the regions are classified into categories of binocular fusion, binocular rivalry and binocular suppression. Bivariate statistics of spatially adjacent Gabor response of image are extracted from each category of regions, based on which features are calculated for image quality representation. In particular, the extraction strategy depends on the type of image patch. Experimental results show that the proposed model is promising at handling the task of SIQA on LIVE 3D Image Quality Database.
Robin Leech - One of the best experts on this subject based on the ideXlab platform.
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CANADIAN-MADE Binoculars, Part 1: Research Enterprises Ltd, 1939-1945 ©
2015Co-Authors: Robin LeechAbstract:At the onset of WWII, the Canadian Government initiated the building of a factory in Leaside, Ontario, to build the first Binoculars ever made in Canada. The Federal Government established Research Enterprises Ltd (REL) as a Crown Corporation. The special optical/binocular glass was developed in Ottawa at the National Research Council (NRC). The machinery and equipment needed to make the binocular bodies was purchased from Bausch & Lomb (B&L), Rochester, NY, for $600,000 in 1940. From 1939 till September 1945, when REL was closed, about 50,000 6X30 and 25,000 7X50 Porro-prism Type I Binoculars were produced. REL binocular lenses were not coated during WWII. Canadian-made Binoculars were not coated with magnesium fluoride (MgF2) till after WWII (1950-1953). Cases were issued for some Binoculars, but not all.
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canadian made Binoculars part 1 research enterprises ltd 1939 1945
2015Co-Authors: Robin LeechAbstract:At the onset of WWII, the Canadian Government initiated the building of a factory in Leaside, Ontario, to build the first Binoculars ever made in Canada. The Federal Government established Research Enterprises Ltd (REL) as a Crown Corporation. The special optical/binocular glass was developed in Ottawa at the National Research Council (NRC). The machinery and equipment needed to make the binocular bodies was purchased from Bausch & Lomb (B&L), Rochester, NY, for $600,000 in 1940. From 1939 till September 1945, when REL was closed, about 50,000 6X30 and 25,000 7X50 Porro-prism Type I Binoculars were produced. REL binocular lenses were not coated during WWII. Canadian-made Binoculars were not coated with magnesium fluoride (MgF2) till after WWII (1950-1953). Cases were issued for some Binoculars, but not all.
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CANADIAN-MADE Binoculars, Part 3: ELCAN roof-prism, military & civilian versions with data on two Fujinon replacements©
2015Co-Authors: Robin LeechAbstract:In 1974, Ernst Leitz Canada received a contract from the Canadian Government to produce 7X50 roof-prism Binoculars for the Canadian Inter-Service Military. Production lasted till 1977. In that time, Ernst Leitz Canada produced 8200 ELCAN roof-prism Binoculars (about 7800 military versions, and about 400 civilian versions). The eyepiece optics are of an Erfle style (glued doublet with 2 air-spaced singlets), and the objectives are two air-spaced singlets. An 8X50 model was designed for the civilian market, but because of poor civilian sales of the 7X50 version, it was not produced. In 1977, Ernst Leitz received a huge contract to produce 10,000 units of a hand-held laser rangefinder, thus ending the ELCAN binocular production. ELCAN 7X50 roof-prism Binoculars are waterproof to 5 m depth, shockproof from 2.44 m onto a hard surface. The military version was issued with yellow filters, rubber ocular and objective lens covers, and a carry case. Later issues were also given a small, zippered case to attach to the neck strap for the filters. The civilian version was issued with rubber ocular and objective lens covers, and a black soft leather carry case with the Leitz® logo. After more than 25 years as the workhorse binocular for the Canadian military, the ELCAN 7X50 roof-prism Binoculars were retired about 1999-2000 in favor of two models of Fujinon Binoculars, both with eye-save (anti-laser) green coating: a 7X50 Porro-prism Type 1, with a right eye reticle and 7 30 ׳ FoV, and 7X30 roof-prism Binoculars with 7 FoV, but no reticle. The ELCAN Binoculars are still used in the Canadian Arctic by the Canadian Rangers. The Canadian Rangers are a subcomponent of the Canadian Armed Forces Reserve. Today, most NCOs purchase their own military versions of Binoculars.
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canadian made Binoculars part 3 elcan roof prism military civilian versions with data on two fujinon replacements
2015Co-Authors: Robin LeechAbstract:In 1974, Ernst Leitz Canada received a contract from the Canadian Government to produce 7X50 roof-prism Binoculars for the Canadian Inter-Service Military. Production lasted till 1977. In that time, Ernst Leitz Canada produced 8200 ELCAN roof-prism Binoculars (about 7800 military versions, and about 400 civilian versions). The eyepiece optics are of an Erfle style (glued doublet with 2 air-spaced singlets), and the objectives are two air-spaced singlets. An 8X50 model was designed for the civilian market, but because of poor civilian sales of the 7X50 version, it was not produced. In 1977, Ernst Leitz received a huge contract to produce 10,000 units of a hand-held laser rangefinder, thus ending the ELCAN binocular production. ELCAN 7X50 roof-prism Binoculars are waterproof to 5 m depth, shockproof from 2.44 m onto a hard surface. The military version was issued with yellow filters, rubber ocular and objective lens covers, and a carry case. Later issues were also given a small, zippered case to attach to the neck strap for the filters. The civilian version was issued with rubber ocular and objective lens covers, and a black soft leather carry case with the Leitz® logo. After more than 25 years as the workhorse binocular for the Canadian military, the ELCAN 7X50 roof-prism Binoculars were retired about 1999-2000 in favor of two models of Fujinon Binoculars, both with eye-save (anti-laser) green coating: a 7X50 Porro-prism Type 1, with a right eye reticle and 7 30 ׳ FoV, and 7X30 roof-prism Binoculars with 7 FoV, but no reticle. The ELCAN Binoculars are still used in the Canadian Arctic by the Canadian Rangers. The Canadian Rangers are a subcomponent of the Canadian Armed Forces Reserve. Today, most NCOs purchase their own military versions of Binoculars.
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CANADIAN-MADE Binoculars, Part 2: BOP & CAL retrofits of RELs in the early 1950s©
2015Co-Authors: Robin LeechAbstract:With the start of the Korean War in June 1950, the Canadian Government found itself without adequate military equipment, including Binoculars. Starting in 1950, and ending in 1953, Canadian Arsenals Ltd (C.A.L.) of Long Branch, Ontario, and Beaconing Optical & Precision Materials (B.O.P.) of Granby, Quebec, were contracted to retrofit remaining or recalled WWII REL 6X30 and 7X50 Binoculars. These retrofit Binoculars were to provide the Canadian troops for the duration of the Korean War. Some of the 7X50s were specially modified by BOP to have internal filters (based on the British WWII 7X50 Barr & Stroud CF41): Very Dark-Dark-YellowClear for both ocular columns. Further, the optics were coated during the retrofits. The external lenses at least were coated in both the BOP and CAL (retrofits) conversions. The 6X30 REL Binoculars were retrofitted with coated optics by CAL, but they underwent fewer visible changes than did the 7X50 REL Binoculars by BOP. The CAL and BOP refits are indicated by the printing on both prism covers. In some cases the original REL prism cover data were deleted, either by being milled out or struck out, and can no longer be read. Often the deleted data are reprinted on another location on the prism covers. The REL 6X30 Binoculars may vary in weight as much as 200g, depending on the materials used (e.g., aluminum vs brass). This is Part 2 of three articles on Canadian-made Binoculars. Part 1 (Leech 2015a) discusses the WWII Research Enterprises Ltd Binoculars made at Leaside, ON, and Part 3 (Leech & Kubetz 2015) discusses the 7X50 ELCAN Binoculars made by Ernst Leitz Canada, of Midland, Ontario. Included is discussion of the ELCAN replacements in 1999/2000 by the 7X30 and 7X50 Fujinon Binoculars which have special optical coatings and anti-laser filters for military use.
Liquan Shen - One of the best experts on this subject based on the ideXlab platform.
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Bivariate analysis of 3D structure for stereoscopic image quality assessment
Signal Processing-image Communication, 2018Co-Authors: Liquan Shen, Ping AnAbstract:Abstract Human visual system (HVS) identifies each unit of stereo-pair into binocular or monocular perception depending on distortions and depth perception. However, these HVS properties still have a large room for exploration in stereoscopic image quality assessment (SIQA) research field. In this paper, a bivariate natural scene statistics (NSS) model is proposed to capture image quality by extracting features from binocular and monocular perception regions, respectively. In the implementation details, the stereo-pair is first segmented into various regions based on spatial information of its disparity. Then the regions are classified into categories of binocular fusion, binocular rivalry and binocular suppression. Bivariate statistics of spatially adjacent Gabor response of image are extracted from each category of regions, based on which features are calculated for image quality representation. In particular, the extraction strategy depends on the type of image patch. Experimental results show that the proposed model is promising at handling the task of SIQA on LIVE 3D Image Quality Database.
Eileen E Birch - One of the best experts on this subject based on the ideXlab platform.
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improved binocular outcomes following binocular treatment for childhood amblyopia
Investigative Ophthalmology & Visual Science, 2018Co-Authors: Krista R Kelly, Reed M Jost, Yizhong Wang, Cynthia L Beauchamp, Joel N Leffler, Eileen E BirchAbstract:Purpose: Childhood amblyopia can be treated with binocular games or movies that rebalance contrast between the eyes, which is thought to reduce depth of interocular suppression so the child can experience binocular vision. While visual acuity gains have been reported following binocular treatment, studies rarely report gains in binocular outcomes (i.e., stereoacuity, suppression) in amblyopic children. Here, we evaluated binocular outcomes in children who had received binocular treatment for childhood amblyopia. Methods: Data for amblyopic children enrolled in two ongoing studies were pooled. The sample included 41 amblyopic children (6 strabismic, 21 anisometropic, 14 combined; age 4-10 years; ≤4 prism diopters [PD]) who received binocular treatment (20 game, 21 movies; prescribed 9-10 hours treatment). Amblyopic eye visual acuity and binocular outcomes (Randot Preschool Stereoacuity, extent of suppression, and depth of suppression) were assessed at baseline and at 2 weeks. Results: Mean amblyopic eye visual acuity (P < 0.001) and mean stereoacuity improved (P = 0.045), and mean extent (P = 0.005) and depth of suppression (P = 0.003) were reduced from baseline at the 2-week visit (87% game adherence, 100% movie adherence). Depth of suppression was reduced more in children aged <8 years than in those aged ≥8 years (P = 0.004). Worse baseline depth of suppression was correlated with a larger depth of suppression reduction at 2 weeks (P = 0.001). Conclusions: After 2 weeks, binocular treatment in amblyopic children improved visual acuity and binocular outcomes, reducing the extent and depth of suppression and improving stereoacuity. Binocular treatments that rebalance contrast to overcome suppression are a promising additional option for treating amblyopia.
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binocular ipad game vs patching for treatment of amblyopia in children a randomized clinical trial
JAMA Ophthalmology, 2016Co-Authors: Krista R Kelly, Reed M Jost, Cynthia L Beauchamp, Joel N Leffler, Eileen E BirchAbstract:Importance Fellow eye patching has long been the standard treatment for amblyopia, but it does not always restore 20/20 vision or teach the eyes to work together. Amblyopia can be treated with binocular games that rebalance contrast between the eyes so that a child may overcome suppression. However, it is unclear whether binocular treatment is comparable to patching in treating amblyopia. Objectives To assess the effectiveness of a binocular iPad (Apple Inc) adventure game as amblyopia treatment and compare this binocular treatment with patching, the current standard of care. Design, Setting, and Participants This investigation was a randomized clinical trial with a crossover design at a nonprofit eye research institute. Between February 20, 2015, and January 4, 2016, a total of 28 patients were enrolled in the study, with 14 randomized to binocular game treatment and 14 to patching treatment. Interventions Binocular game and patching as amblyopia treatments. Main Outcomes and Measures The primary outcome was change in amblyopic eye best-corrected visual acuity (BCVA) at the 2-week visit. Secondary outcomes were change in stereoacuity and suppression at the 2-week visit and change in BCVA at the 4-week visit. Results Among 28 children, the mean (SD) age at baseline was 6.7 (1.4) years (age range, 4.6-9.5 years), and 7 (25%) were female. At baseline, the mean (SD) amblyopic eye BCVA was 0.48 (0.14) logMAR (approximately 20/63; range, 0.3-0.8 logMAR [20/40 to 20/125]), with 14 children randomized to the binocular game and 14 to patching for 2 weeks. At the 2-week visit, improvement in amblyopic eye BCVA was greater with the binocular game compared with patching, with a mean (SD) improvement of 0.15 (0.08) logMAR (mean [SD], 1.5 [0.8] lines) vs 0.07 (0.08) logMAR (mean [SD], 0.7 [0.8] line; P = .02) after 2 weeks of treatment. These improvements from baseline were significant for the binocular game (mean [SD] improvement, 1.5 [0.8] lines; P P = .006). Depth of suppression improved from baseline at the 2-week visit for the binocular game (mean [SD], 4.82 [2.82] vs 3.24 [2.87]; P = .03) and for patching (mean [SD], 4.77 [3.10] vs 2.57 [1.67]; P = .004). Patching children crossed over to binocular game treatment, and all 28 children played the game for another 2 weeks. At the 4-week visit, no group difference was found in BCVA change, with children who crossed over to the binocular games catching up with children treated with binocular games, for a mean (SD) improvement of 0.17 (0.10) logMAR (mean [SD], 1.7 [1.0] lines) for the binocular game vs a mean (SD) improvement of 0.16 (0.12) logMAR (mean [SD], 1.6 [1.2] lines) for the patching crossover ( P = .73). Conclusions and Relevance A binocular iPad game was effective in treating childhood amblyopia and was more efficacious than patching at the 2-week visit. Binocular games that rebalance contrast to overcome suppression are a promising additional option for treating amblyopia. Trial Registration clinicaltrials.gov Identifier:NCT02365090.
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normative reference ranges for binocular summation as a function of age for low contrast letter charts
Strabismus, 2014Co-Authors: Stacy L Pineles, Joseph L. Demer, Federico G Velez, Fei Yu, Eileen E BirchAbstract:AbstractPurpose: Binocular summation (BiS), defined as the superiority of binocular over monocular viewing on visual threshold tasks, is most often studied in laboratory settings. Few studies have evaluated BiS with readily available clinical tools. Low contrast acuity (LCA) charts are increasingly popular in clinical research, yet their utility in detecting BiS has not been evaluated.Methods: 129 normal subjects aged 3 to 85 years were prospectively enrolled and underwent monocular and binocular testing using 2.5% and 1.25% Sloan LCA charts and Pelli-Robson (PR) contrast sensitivity (CS) charts at an academic institution. Subjects also underwent similar testing with Early Treatment Diabetic Retinopathy Study (ETDRS) VA charts. BiS was calculated as the difference between the better eye and binocular scores.Results: Monocular and binocular scores decreased with increasing age for all metrics. The mean (±SD) BiS scores for 2.5% and 1.25% Sloan LCA were 6 ± 4.5 and 3 ± 5 letters, respectively. BiS score was...
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binocular ipad treatment for amblyopia in preschool children
Journal of Aapos, 2014Co-Authors: Eileen E Birch, Reed M Jost, Simone L Li, Sarah E Morale, Angie De La Cruz, David R StagerAbstract:Background Recent experimental evidence supports a role for binocular visual experience in the treatment of amblyopia. The purpose of this study was to determine whether repeated binocular visual experience with dichoptic iPad games could effectively treat amblyopia in preschool children. Methods A total of 50 consecutive amblyopic preschool children 3-6.9 years of age were assigned to play sham iPad games (first 5 children) or binocular iPad games (n = 45) for at least 4 hours per week for 4 weeks. Thirty (67%) children in the binocular iPad group and 4 (80%) in the sham iPad group were also treated with patching at a different time of day. Visual acuity and stereoacuity were assessed at baseline, at 4 weeks, and at 3 months after the cessation of game play. Results The sham iPad group had no significant improvement in visual acuity ( t 4 = 0.34, P = 0.75). In the binocular iPad group, mean visual acuity (plus or minus standard error) improved from 0.43 ± 0.03 at baseline to 0.34 ± 0.03 logMAR at 4 weeks (n = 45; paired t 44 = 4.93; P t 44 = 1.35, P = 0.18). Children who played the binocular iPad games for ≥8 hours (≥50% compliance) had significantly more visual acuity improvement than children who played 0-4 hours ( t 43 = 4.21, P = 0.0001). Conclusions Repeated binocular experience, provided by dichoptic iPad game play, was more effective than sham iPad game play as a treatment for amblyopia in preschool children.
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treatment of bilateral refractive amblyopia in children three to less than 10 years of age
American Journal of Ophthalmology, 2007Co-Authors: David K Wallace, Eileen E Birch, Danielle L Chandler, Roy W Beck, Robert W Arnold, Darron A Bacal, Joost Felius, Marcela Frazier, Jonathan M Holmes, Darren L HooverAbstract:Purpose To determine the amount and time course of binocular visual acuity improvement during treatment of bilateral refractive amblyopia in children three to less than 10 years of age. Design Prospective, multicenter, noncomparative intervention. Methods One hundred and thirteen children (mean age, 5.1 years) with previously untreated bilateral refractive amblyopia were enrolled at 27 community- and university-based sites and were provided with optimal spectacle correction. Bilateral refractive amblyopia was defined as 20/40 to 20/400 best-corrected binocular visual acuity in the presence of 4.00 diopters (D) or more of hypermetropia by spherical equivalent, 2.00 D or more of astigmatism, or both in each eye. Best-corrected binocular and monocular visual acuities were measured at baseline and at five, 13, 26, and 52 weeks. The primary study outcome was binocular acuity at one year. Results Mean binocular visual acuity improved from 0.50 logarithm of the minimum angle of resolution (logMAR) units (20/63) at baseline to 0.11 logMAR units (20/25) at one year (mean improvement, 3.9 lines; 95% confidence interval [CI], 3.5 to 4.2). Mean improvement at one year for the 84 children with baseline binocular acuity of 20/40 to 20/80 was 3.4 lines (95% CI, 3.2 to 3.7) and for the 16 children with baseline binocular acuity of 20/100 to 20/320 was 6.3 lines (95% CI, 5.1 to 7.5). The cumulative probability of binocular visual acuity of 20/25 or better was 21% at five weeks, 46% at 13 weeks, 59% at 26 weeks, and 74% at 52 weeks. Conclusions Treatment of bilateral refractive amblyopia with spectacle correction improves binocular visual acuity in children three to less than 10 years of age, with most improving to 20/25 or better within one year.
Siti Khoiruli Ummah - One of the best experts on this subject based on the ideXlab platform.
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Development Of Smart Binoculars Learning For Trigonometry Materials In Middle Vocational School
Mathematics Education Journal, 2020Co-Authors: Ferry Kurniawan, Moh. Mahfud Effendi, Siti Khoiruli UmmahAbstract:The purpose of this research is to develop smart Binoculars learning media for trigonometry material in Vocational Schools so that it can help and facilitate mathematics teachers in explaining one of the concepts of trigonometry material. The type of research used in this research is Research and Development (R&D) while the development of instructional media refers to the modified Borg and Gall model, namely research and collection, planning, product draft development, expert validation, small-scale trials. The development has three criteria, namely valid, practical and effective. The results showed that obtained from filling out the validation sheet by the material expert and media expert validators were in the valid category. Furthermore, the practicality of smart Binoculars learning media based on student response questionnaire the average student is satisfied with the learning experience using learning media and for the effectiveness of smart Binoculars learning media get positive things because the evaluation of ten samples of students gets grades above minimal completeness criteria.