Prototypes of motorized-focus telescopes (MFTs) and of a 4X auto-focus telescope (AFT) were constructed, and 22 users of hand-focus telescopes (HFTs) were trained to use them for near-distance and intermediate-distance tasks. Despite the lack of differences in performance with the MFT, AFT, and HFT, the subjects’ ratings on 9 of 10 aspects of telescope performance were significantly higher for the AFT and MFT than for the HFT.
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References
1.
AppleM.E., AppleL.E., & BlaschD. (1980). Low vision. In WelshR.L., & BlaschB.B. (Eds.), Foundations of orientation and mobility.New York: American Foundation for the Blind.
2.
BergR.V., JoseR.T., & CarterK. (1983). Distance training techniques. In JoseR. (Ed.), Understanding low vision (pp. 277–316). New York: American Foundation for the Blind.
3.
DemerJ.L., & AmjadiF. (1993). Dynamic visual acuity of normal subjects during vertical optotype and head motion.Investigative Ophthalmology and Visual Science, 34, 1894–1906.
4.
DemerJ.L., GoldbergJ., PorterF.I., & SchmidtK. (1991). Validation of physiologic predictors of successful telescopic spectacle use in low vision.Investigative Ophthalmology and Visual Science, 32, 2826–2834.
5.
DemerJ.L., PorterF.I., GoldbergJ., JenkinsH.A., SchmidtK., & UlrichI. (1989). Predictors of functional success in telescopic spectacle use by low vision patients.Investigative Ophthalmology and Visual Science, 30, 1652–1665.
6.
KuykT., & JamesJ. (1990). A pilot study of a telescopic low vision aid with motorized focus.Journal of Vision Rehabilitation, 4, 21–29.
7.
QuillmanR.D. (1977). Utilization of telescopic lenses in low vision mobility.Long Cane News, 10, 3–9.
8.
WatsonG., BeckS., StelmackJ., MainoJ., & De l'AuneW. (1994). A national survey of the impact of low vision device use among veterans (Final report of project C639-RA).Washington, DC: Department of Veterans Affairs, Rehabilitation Research and Development Service.
9.
WienerW., & WopataA. (1980). Suggested curriculum for distance training with optical aids.Journal of Visual Impairment & Blindness.74, 49–56.
