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Compound lenses

For compound lenses, as in a single-lens reflex camera, the focal lengths add as follows ... [Pg.87]

Cellulose esters of butyric and propionic acids have limited adhesive use. However, cellulose caprate, having a refractive index near that of glass and good resistance to photochemical change, is a useful hotmelt optical cement for the manufacture of compound lenses. [Pg.292]

Optical dispersion n. Of a transparent material, the difference between the refractive indices of the material for two different wavelengths of hght in particular, the wavelengths of red and violet lights (ca. 650 and 410nm, respectively). Dispersion is an important property in the design of compound lenses. [Pg.679]

Optofluidic Compound Lenses Made with Ionic Liquids. [Pg.497]

FIGURE 3-21. Compound lens for correction of chromatic aberration. [Pg.72]

Fig. 16. Diagram showing a compound lens forming an image. Figure not to scale. Fig. 16. Diagram showing a compound lens forming an image. Figure not to scale.
Fig. 17. Photographs showing the images of a pinhole (star), placed at 3 m, given by a twocell compound lens under different negative and positive pressure. First cell had a pressure of 1 oz/ inch. Second cell had different pressures (a) 3 inch Hg, (b) 2 inch Fig, (c) zero pressure, (d) 3 oz/inch, (e) 5 oz/ inch, (f) 7 oz/inch. ... Fig. 17. Photographs showing the images of a pinhole (star), placed at 3 m, given by a twocell compound lens under different negative and positive pressure. First cell had a pressure of 1 oz/ inch. Second cell had different pressures (a) 3 inch Hg, (b) 2 inch Fig, (c) zero pressure, (d) 3 oz/inch, (e) 5 oz/ inch, (f) 7 oz/inch. ...
The two-cell compound lens was also tested to find the possibility to form images of nearby objects. An USAF test chart was placed about 2 cm away from the cell. Then a pressure of 1 psi was given to the first cell and a pressure of 11 oz/inch was given to the second cell. Image was studied with a microscope and is seen in Fig. 19. We can notice that element 3 in group 5 of the test chart can be seen. This means that about 40 Ip/mm can be resolved. [Pg.513]

We have described the characterization studies made to the membranes. Parameters like roughness and profiles under pressure have been exposed. A study of the membrane profiles tell us that their deviation from a theoretical circle is small. Also it was shown that cells were able to form images. Besides this a two-cell compound lens was assembled. This compound lens gave images with different sizes when the pressure on one cell was changed. [Pg.514]

In section 4, we have shown an optical design study of a 3 cell compound lens. Liquids considered were ionic liquids. From the theoretical point of view (diffraction limited behavior) optical behavior of this three-cell lens is good. Flowever, the fabrication of such a three cell compound lens needs the development of more accurate fabrication methods. Probably with MEMS technology the three cell compound lens could be made. With our low-technology method, comprising acrylic cells, just a two-cell compound lens with diameters of some millimeters can be done. [Pg.514]

PEROXIDES AND PEROXIDE COMPOUNDS - INORGANICPEROXIDES] (Vol 18) -contact lens correction [CONTACT LENSES] (Vol 7)... [Pg.503]

Sulfides, thiols, and proteinacious organic matter, particularly plasma and whole blood, seriously depress and may even aboHsh the germicidal action of mercury compounds (qv). As of this writing approved uses for mercurials are limited to contact lens cleaning fluids, spoilage prevention of stored... [Pg.135]

Vision is vital for human activities, and eyes are very sensitive to a number of toxic insults induced by chemical compounds. The most serious outcome is permanent eye damage which may be so severe as to cause loss of vision. The eye consists of the cornea and conjunctiva, the choroid, the iris, and the ciliary body. It also contains the retina, which is of neural origin, and the optic nerve. The retina contains photoreceptors, a highly specific light-sensitive type of neural tissue. The eye also contains the lens and a small cerebrospinal fluid system, the aqueous humor system, that is important for the maintenance of the steady state of hydration of the lens and thus the transparency of the eye. [Pg.292]

Attached by a covalent bond to carbon atom 1 of the deoxyribose ring is an amine (and therefore a base), which may be adenine, A (22) guanine, G (23) cytosine, C (24) or thymine, T (25). In RNA, uracil, U (26), replaces thymine. The base bonds to carbon atom 1 of deoxyribose through the nitrogen of the —NH— group (printed in red) and the compound so formed is called a nucleoside. All nucleosides have a similar structure, which we can summarize as the shape shown in (27) the lens-shaped object represents the attached amine. [Pg.895]

This preservative is comparatively new to ophthalmic preparations and is a polymeric quaternary ammonium germicide. Its advantage over other quaternary ammonium seems to be its inability to penetrate ocular tissues, especially the cornea. It has been used at concentrations of 0.001-0.01% in contact lens solutions as well as dry eye products. At clinically effective levels of preservative, POLYQUAD is approximately 10 times less toxic than benzalkonium chloride [87,137], Various in vitro tests and in vivo evaluations substantiate the safety of this compound [137,141,142], This preservative has been extremely useful for soft contact lens solutions because it has the least propensity to adsorb onto or absorb into these lenses, and it has a practically nonexistent potential for sensitization. Its ad-sorption/absorption with high water and high ionic lenses can be resolved by carefully balancing formulation components [143],... [Pg.434]

This preservative is also comparatively new to ophthalmic formulations and has been used as a disinfectant in contact lens solutions. Polyaminopropyl biguanide (polyhexamethyl biguanide) also is a polymeric compound that has a low toxicity potential at the concentrations generally used in these solutions [141, 149, 150]. [Pg.435]

Elimination from the vitreous occurs by one of two pathways. This can be visualized by injecting fluorescent compounds and examining the concentration distribution in frozen sections obtained after a steady state has been established [230]. If the major route of elimination is by means of the re-tina/choroid, at steady state the lowest concentration would be in the vicinity of the retina. The contours observed in frozen sections of the rabbit eye obtained after intravitreal injection of fluorescein exhibit this pattern, with the highest concentration immediately behind the lens (Fig. 16A). Compounds not chiefly eliminated through the retina exit the vitreous by passive diffusion and enter the posterior aqueous, where they are eliminated by the natural production and outflow of aqueous humor. In such a situation, the contours would be perpendicular to the retina, with the highest concentration towards the rear of the vitreous cavity. This appears to be the case for fluorescently labeled dextran polymer, whose contours decrease in concentration toward the hyaloid membrane (Fig. 16B). [Pg.447]

The compound microscope is essentially a two-stage magnifier. One lens (or combination of lenses), termed the objective, forms a real image of an illuminated or self-luminous object, and a second lens (or combination of lenses), denoted as the eyepiece, acts as a simple magnifier whose object is the real image formed... [Pg.131]

Herrygers, V., H. van Langenhove, and E. Smet (2000), Biological treatment of gases polluted by volatile sulfur compounds. In P.N. L. Lens and L. H. Pol (eds.), Environmental Technologies to Treat Sulfur Pollution — Principles and Engineering, IWA Publishing, pp. 281—304. [Pg.167]

It is some 15 years since the writer first experienced myosis with D.F.P. and related compounds, and one difference now noted during myosis is that white surfaces appear yellow. This phenomenon may well be due to changes in lens structure in the region of the optic axis. [Pg.82]


See other pages where Compound lenses is mentioned: [Pg.695]    [Pg.71]    [Pg.72]    [Pg.127]    [Pg.495]    [Pg.149]    [Pg.694]    [Pg.103]    [Pg.429]    [Pg.430]    [Pg.432]    [Pg.72]    [Pg.212]    [Pg.495]    [Pg.496]    [Pg.510]    [Pg.510]    [Pg.518]    [Pg.328]    [Pg.181]    [Pg.64]    [Pg.32]    [Pg.129]    [Pg.307]    [Pg.285]    [Pg.244]    [Pg.434]    [Pg.474]    [Pg.350]    [Pg.97]    [Pg.38]    [Pg.132]    [Pg.38]    [Pg.1375]    [Pg.364]    [Pg.38]    [Pg.244]    [Pg.527]   
See also in sourсe #XX -- [ Pg.200 ]




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