The early history of optics and vision science (older term: physiological optics) is indeed fascinating. The earliest known true lenses have been found in "eyes" of Egyptian statues which contain superb, complex, and well-polished eye-lens units. The oldest ones known are dated circa 2575 BCE = BC, Dynasty IV, Old Kingdom. These eye-lens units induce a fascinating and powerful visual illusion, but they are just too good to have been the first lenses, or even the first lenses of this design! So saying, no earlier dateable lenses have been found in Egypt or elsewhere. Recently, at the Boston Museum of Fine Arts, the writer noted a previously undetected lens in this series (a first in the Western Hemisphere). Oddly, dateable simpler magnifying lenses and burning glasses seem to have appeared later in time (?)! Manufactured mirrors are quite a bit older, dating from circa 6000 BCE in atal Hyk, located in south-central modern-day Turkey. Using these ancient mirrors, the image quality obtained is remarkable! Recently discovered ancient artificial eyes, located, in situ, in exhumed corpses, have been dated circa 3000 BCE (one discovered in Iran) and 5000 BCE (one found in Spain). On the 3000 BCE artificial eye, there are drawn light rays (the writer believes these to be the oldest known depiction of light rays!) spreading out from (or passing into) the iris/ pupil border! Added interesting aspects associated with the early development of light-rays are considered. Thus, early optics can be readily traced back to the Neolithic era (the new stone age), and in some cases before that time period. We have deep roots indeed!
Some years ago, the speaker demonstrated that vertebrate retinal photoreceptors are fiber optics
elements and waveguides, and he succeeded in defining many of their properties. For a summary of
much of this research, please see the reference to Enoch and Tobey listed below (Reference 4).
Included are studies of photo-receptor alignments and maintenance of receptor alignments across the
retina in normal and abnormal human eyes. With very rare exceptions, rod and cone photoreceptors
across the retina align remarkably and precisely with the center-of-the-exit-pupil-of-the-optics-ofthe-
eye throughout the lifetime of the individual! And within a modest period of time (a day or a bit
more), it proved possible to alter that photoreceptor alignment by physically displacing the pupillary
aperture; and with recentration of the eye pupil, these alignments recovered their original state.
Here, the author asks, "Might advantage be gained by developing alignment sensitive, photoactivated,
waveguide/fiber optic units? That is, might comparable mechanisms be adapted in a
useful manner to non-biological fiber-optics applications? Since such characteristic responses have
been clearly of great value for biological species; might similar designs serve other important
roles?"
We propose a new stress-sensing technique based upon measurement of light scattering produced by an array of birefringent waveguides. When external stress is applied to the array of waveguides, their optical properties are modified via the photo-elastic effect. By monitorizing the scattered light amplitude this change can be detected and analyzed in order to assess the strength and direction of the external force.
The first known lenses appeared during the IVth and Vth Dynasties (fabricated mainly between ca. 2500 - 2400 BC) of the Old Kingdom of Egypt. Excellent examples of these lenses are found in The Louvre Museum in Paris and the Egyptian Museum in Cairo. These lenses were components of eye constructs in statues and had unique qualities. In particular, the `eyes' appear to follow the viewer as he/she rotates about the statues in any direction. Clearly, this was an intended effect which can be readily photographed (and understood optically). The lenses were ground from high quality rock crystal (a form of quartz). They had a convex and highly polished front surface. On the plane rear lens surface as `iris' was painted. Centered in the dark- appearing pupil zone was an approximately hemispheric negative ground, high power, concave lens surface.
The early history of lenses is controversial. The author has sought to address the problem by identifying lens elements (mainly convex/plano) which remain associated with objects intended to be viewed through them (i.e., in their original context). These are found in museums in sculptures, rings, pendants, etc. A number of outstanding examples will be illustrated in the talk; these sophisticated pieces of art are certainly not first constructs. Most are of rock crystal, rose quartz, or glass. Lenses have origin among artisans rather than scientists. Clearly, skills were often lost and rediscovered. Early lens-like objects have been found broadly in the eastern Mediterranean area/Middle East, in France, in Italy (Rome), and possibly in Peru and Scandinavia, etc. To date, the earliest lenses identified in context are from the IV/V Dynasties of Egypt, dating back to about 4500 years ago (e.g., the superb `Le Scribe Accroupi' and `the Kai' in the Louvre; added fine examples are located in the Cairo Museum). Latter examples have been found in Knossos (Minoan [Herakleion Museum]; ca. 3500 years ago); others had origin in Greece (examples in the Athens National Archeological Museum and the British Museum equals BM), in Rome (Metropolitan Museum, NY; BM; Vatican Museums; Bologna Archeological Museum), etc. Also. of great interest is the study of possible lens applications. This is a fascinating scientific, artistic and intellectual project.
There is a need for precise visual functional analysis that parallels and complements the advance technologies employed in ophthalmic surgery. An instrument is needed which can be coupled to the surgical device which allows precision assessment of vision in some sub portion of the cornea, the entire area of surgical intervention, and the entire cornea. A device is proposed for inclusion which allows (1) monitoring and control of fixation during surgery and visual assessment, (2) precision alignment of the corneal surgical area and the eye lens with the point of fixation (using an achromatic axis), (3) focusing, locating, adjusting, and monitoring an aperture image in the surgical plane, (4) provision of any desired test of vision, and (5) measurement and correction of refractive error and certain aberrations as often as required. The utilization of the hyperacuity paradigms as part of the test battery are also suggested. These can be highly precise reliable benchmarks for characterizing refractive surgery. Hyperacuity testing is well suited for analysis of visual performance in relation to keratorefractive surgery because the procedure is highly resistant to optical image degradation and requires a higher-order analysis by the visual system. The uses of hyperacuity techniques are discussed. These techniques allow assessment of vision through cloudy, distorted, or absorbing optical media, and it is possible to separate quantitatively optical from neural decrements in visual performance. These techniques allow fine detection and measurement of distortion and metamorphopsia. Hyperacuity is also used for precision alignment of the optical elements of the eye and the fovea.
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