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This Dissertation Has Been 64-9559 Microfilmed Exactly As Received INVESTIGATION of the HOROPTER and the Ohio State University

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This Dissertation Has Been 64-9559 Microfilmed Exactly As Received INVESTIGATION of the HOROPTER and the Ohio State University This dissertation has been 64-9559 microfilmed exactly as received ESKRIDGE, Jess Boyd, 1 9 2 8 - INVESTIGATION OF THE HOROPTER AND THE APPARENT FRONTAL PLANE. The Ohio State University, Ph.D., 1964 Physiology University Microfilms, Inc., Ann Arbor, Michigan INVESTIGATION OP THE HOROPTER AND THE APPARENT FRONTAL PLANE DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By JESS BOYD ESKRIDGE, B.Se., M. Opt., M.Sc. ****** The Ohio State University 1964 Approved by: ISLXJKAAA/\ v/\ • rv Ad vise i* School of Optometry ACKNOWLEDGMENTS A list of those individuals who have aided me in the attainment of this goal would indeed be long, and the acknowledgment of each would be impractical. I would be amiss, however, if I did not give special recognition and express my sincere appreciation to these few. I am grateful to Dr. Fred Hebbard for his interest and for the incentive that he gave me to begin graduate study, to the members of the American Optometric Foundation for the Research Fellowship awarded me made it possible for me to pursue this program, and to Dickson Call and the staff at the Ohio State University Numerical Computation Laboratory for their assistance in programming and operating the 1620 IBM computer. Only those who have "trod this path" can fully appre­ ciate the encouragement, guidance, and help given by my adviser, Dr. Glenn A. Fry. His devotion and the unselfish giving of his time, effort, and knowledge have been and will always be a stimulating example to those that know him. In an undertaking such as this, the support and interest of wife and family are invaluable, and I want to gratefully acknowledge the constant encouragement and assistance given by my wonderful wife, Beth, and my children, Chris and Cheryl. ii CONTENTS Page INTRODUCTION..................................... 1 APPARATUS .............................................. 9 METHOD OF ANALYZING D A T A ............................... 30 EFFECT OF CHANGE IN FIXATION DISTANCE ON THE HOROPTER AND THE APPARENT FRONTAL PL A N E ............ 35 EFFECT OF PROLONGED WEARING OF MERIDIONAL MAGNIFIERS ON THE HOROPTER AND THE APPARENT FRONTAL PLANE . 88 EFFECT OF ASYMMETRICAL CONVERGENCE ON THE HOROPTER, THE APPARENT FRONTAL PLANE, AND THE APPARENT NORMAL PLANE ............................................ 108 SUMMARY AND C O N C L U S I O N S ..................................128 BIBLIOGRAPHY...............................................133 AUTOBIOGRAPHY ............................................ 135 111 FIGURES Figure Page 1. Hie horopter according to Aguilonis............ 3 2. The horopter according to Vieth and Mfiller . 4 3. Apparatus used to determine the horopter . 10 Diagram of the apparatus vised to determine the horopter ........ ........ ...... 11 5* Diagram of the slides used to determine the horopter and the apparent frontal plane . 15 6. Apparatus used to determine the apparent frontal plane and apparent normal plane . 17 7. Diagram of the apparatus used to determine the apparent frontal plane and apparent normal plane............................... 18 8. Diagram showing relation between size of the target and the apparent angular displacement of the target at the entrance pupil of the eye. 21 9. Apparatus used to calibrate separation of lenses and the apparent angular displacement of the target at the entrance pupil of the eye. 22 10. Ratio of the apparent angular displacement of the target to the linear dimension of the target as a function of the lens separation . 24 11. Apparatus used to calibrate the target-prism separation and the displacement of the eccentrically located fixation line .......... 25 12. Apparent separation of target elements as a function of target-prism separation .......... 28 13. Diagram showing Vleth-Mttller Circle, objective frontal plane, and angles used in analyzing d a t a ........................... .......... 31 iv FIGURES— Continued Figure Page 14. Horopter apparatus of Ames et al ................... 36 15. Screens used In grid-nonius method of Ames et a l ................................................ 37 16. Binocular appearance of wires In grld-nonius m e t h o d .......................... 3d 17. Horopter data of Ames et al. with fixation distance of 75-6 c m ............................... 40 18. Horopter data of Ames et al. with fixation distance of 40.4 cm ........................... 41 1 9. Horopter data of Ames et al. with fixation distance of 20.2 c m ............................... 42 20. Analytical graph of horopter data of Ames et al. with fixation distance of 75*6 c m ................ 43 21. Analytical graph of horopter data of Ames et al. with fixation distance of 40.4 c m ................ 44 22. Analytical graph of horopter data of Ames et al. with fixation distance of 20.2 c m ................43 2 3. Hering-Hlllebrand deviation of the horopter data of Ames et a l . as a function of the fixation distance ............................... 46 24. Horopter data with parallel lines of sight . 51 25. Horopter data with fixation distance of 100 cm . 52 26. Horopter data with fixation distance of 5 0 cm . 53 2 7. Horopter data with fixation distance of 25 cm . 54 28. Horopter data with fixation distance of 16.66 c m .......................................... 55 29. Horopter data for all fixation distances .... 5 6 v FIGURES— Continued Figure Page 30. Number of retinal elements per unit length as a function of linear distance from the fovea determined from Osterberg*s d a t a .............. 53 31. Analytical graph of horopter d a t a ................ 61 32. Hering-Hillebrand deviation of the apparent frontal plane as a function of the fixation distance for data of Zajaczkowska, Helmholtz, and Ames et al.......................65 33- Apparent frontal plane data with parallel lines of s i g h t ............................... 69 34. Apparent frontal plane data with fixation distance of 100 c m ........................... 70 35* Apparent frontal plane data with fixation distance of 50 c m ............................. 71 3 6. Apparent frontal plane data with fixation distance of 25 c m ............................. 72 3 7. Apparent frontal plane data with fixation distance of 16.66 c m ................. 73 3 8. Analytical graphs of apparent frontal plane data for fixation distances of infinity, 100 cm, 50 cm, and 25 c m .......................75 39. Analytical graphs of apparent frontal plane data for fixation distance of 16.66 cm .... 76 40. Analytical graph of apparent frontal plane data for all fixation distances................ 77 41. Hering-Hillebrand deviation of the apparent frontal plane as a function of fixation d i s t a n c e ..................................... 78 vi FIGURES— Continued Figure Page 42. Apparent frontal plane data with fixation distance of 40 cm using horopter apparatus . 79 43. Analytical graph of apparent frontal plane data using horopter apparatus with fixation distance of 40 cm ................................ 80 44. Hering-Hillebrand deviation of the apparent frontal plane and the horopter as a fvinetion of fixation for data of Ames et al ............... 83 45. Diagram to explain Fry's concept of the relation of the horopter to perceived object position ................................. 85 46. Percent magnification needed f W apparent frontal plane determinations using the horopter apparatus during the prolonged wearing of a meridional magnifier. From B u r l a n .......................................... 90 47. Percent image size difference measured with the ophthalmoeikonometer and space elkonometer during the prolonged wearing of a meridional magnifier. From M i l e s ........................ 92 48. Percent difference in magnification needed for apparent frontal plane determination during the prolonged wearing of a meridional m a g n i f i e r .......................................... 102 4 9. Percent difference in magnification needed for horopter determinations during the prolonged wearing of a meridional magnifier ................ 104 50. Reference planes during asymmetrical convergence. F ... F' frontal plane, N ... N* normal p l a n e ...............................................109 51. Horopter and apparent normal plane data with symmetrical and asymmetrical convergence. From Herzau and O g l e .............................113 vli FIGURES— Continued Figure Page 52. Spatial plot of horopter and apparent normal plane data with symmetrical and asymmetrical convergence. From Herzau and O g l e ............ 116 53. Horopter data with symmetrical and asymmetrical convergence ................................. 118 54. Apparent frontal plane and apparent normal plane data with symmetrical convergence and 4° of asymmetrical convergence................ 120 55. Apparent frontal plane and apparent normal plane data with symmetrical convergence and 10° of asymmetrical convergence . ............ 121 5 6. Analytical graphs of apparent normal plane data with symmetrical convergence and 4° and 10° of asyranetrical convergence............ 123 57. Spatial plot of apparent normal plane and apparent frontal plane data with sym­ metrical and 10° asymmetrical convergence . 126 viil INTRODUCTION When an object Is placed in the visual field, the observer Is aware that it has a brightness, a color, a shape, and a specific direction in space. The directional attribute of this visual percept Is presumably due to the fact that each retinal area Is connected to a specific cortical area and that
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