# Dispersive Sentence Examples

- On the other hand, while in the older crown and flint glasses the relation between refraction and dispersion had been practically fixed, dispersion and refraction increasing regularly with the density of the glass, in some of the new glasses introduced by Abbe and Schott this relation is altered and a relatively low refractive index is accompanied by a relatively high dispersion, while in others a high refractive index is associated with low
**dispersive**power. - The further they depart from the ratio of refractive index to
**dispersive**power found in the older glasses, the greater the difficulty found in obtaining them of either sufficient purity or stability to be of practical use. - - The optical desideratum is uniformity of refractive index and
**dispersive**power throughout the mass of the glass. - The symbol v represents the inverse of the
**dispersive**power, its value being (nD-i)/(C-F). - The spectrum will be straight if the twoprismsaresimilar in
**dispersive**property, but if one of them is con structed of a material which possesses any peculiarity in this respect it will be revealed by the curvature of the spectrum. - The phenomenon of dispersion shows that in
**dispersive**media the velocity is different for lights of different wave-lengths. - The
**dispersive**powers of gases are, however, generally comparable with those of liquids and solids. - If the refracting angleof the prism is small, then the ratio of the dispersion to the mean deviation of the two rays is the
**dispersive**power of the material of the prism. - If we denote its deviation by S D, then we may put
**Dispersive**power = (F - Sc)/S D. - This gives at once
**Dispersive**power= F - µc)/(y D - I). - The second of these two expressions is generally given as the definition of
**dispersive**power. - Glasses can now be made differing considerably both in refractivity and
**dispersive**power. - The irrationality of dispersion is well illustrated by C.Christiansen's experiments on the
**dispersive**properties of white powders. - These effects are due to the difference in
**dispersive**power of the powder and the liquid. - Thus the ether within the
**dispersive**medium is loaded with molecules which are forced to perform oscillations of the same period as that of the transmitted wave. - Opticians should supply sufficient information of the
**dispersive**properties of their materials to allow dµ/dX to be calculated easily for different parts of the spectrum. - Kundt,' who initiated this line of investigation, came to the conclusion that the absorption spectra of certain organic substances like cyanin and fuchsin were displaced towards the red by the solvent, and that the displacement was the greater the greater the
**dispersive**power of the solvent. - This law cannot be maintained in its generality, but nevertheless highly
**dispersive**substances like carbon bisulphide are always found to produce a greater shift than liquids of smaller dispersion like water and alcohol. - The primary reason for this retention is that nothing approaching the difference in
**dispersive**power between ordinary crown glass and ordinary dense flint glass (a difference of i to 13) has yet been obtained between any pair of the newer glasses. - The figures given are the partial dispersions for ordinary crown and ordinary extra dense flint glasses, styled in Messrs Schott's catalogue of optical glasses as o 60 and 0.102 respectively, having refractive indices of 1 5179 and 1.6489 for the D ray respectively, and (µ D -I)/(l F -µc) =60 2 and 33.8 respectively to indicate their
**dispersive**powers (inverted), = v. - This case well illustrates the much closer approach to strict rationality of dispersion which is obtainable by using two different sorts of glass for the two positive lenses, even when one of them has a higher
**dispersive**power than the glass used for the negative lens. - If there be refraction at a collective spherical surface, or through a thin positive lens, 0' 2 will lie in front of O' 1 so long as the angle u2 is greater than u 1 (" under correction "); and conversely with a
**dispersive**surface or lenses (" over correction "). - If the refractive index for one colour be n, and for another and the powers, or reciprocals of the focal lengths, be 4) and 4)+4, then (I) dï¿½/ 4) = dn/ (n - I) =1 /v; do is called the dispersion, and v the
**dispersive**power of the glass. - Therefore 4) 1 and 42 must have different algebraic signs, or the system must be composed of a collective and a
**dispersive**lens. - Consequently the powers of the two must be different (in order that 4) be not zero (equation 2)), and the
**dispersive**powers must also be different (according to 4). - Newton failed to perceive the existence of media of different
**dispersive**powers required by achromatism; consequently he constructed large reflectors instead of refractors. - Of crown glass and a
**dispersive**lens II. - Of flint glass must be chosen; the latter, although the weaker, corrects the other chromatically by its greater
**dispersive**power. - For an achromatic
**dispersive**lens the converse must be adopted. - To the greater power belongs the weaker
**dispersive**power (greater v), that is to say, crown glass; consequently the crown glass must have the greater refractive index for astigmatic and plane images. - In all earlier kinds of glass, however, the
**dispersive**power increased with the refractive index; that is, v decreased as n increased; but some of the Jena glasses by E. - If its chromatic effect (d4/4) be greater than that of the same lens, this being made of the more
**dispersive**of the two glasses employed, it is termed " hyper-chromatic." - In this primitive Pneuma there must reside the utmost tension and heat; for it is a fact of observation that most bodies expand when heated, whence we infer that there is a pressure in heat, an expansive and
**dispersive**tendency. - In consequence of its low refractive and
**dispersive**power, colourless pellucid fluor-spar is valuable in the construction of apochromatic lenses, but this variety is rare. - Differences of refractive index produce their greatest
**dispersive**effects when incidence on the refracting surface is nearly tangential. - It appears that Newton made the mistake of supposing that all prisms would give a spectrum of exactly the same length; the objections of his opponents led him to measure carefully the lengths of spectra formed by prisms of different angles and of different refractive indices; and it seems strange that he was not led thereby to the discovery of the different
**dispersive**powers of different refractive substances. - On the whole, there is probably no treatise so masterly as Aristotle's Ethics, and containing so much close and valid thought, that yet leaves on the reader's mind so strong Transi= an impression of
**dispersive**and incomplete work. - Lord Rayleigh has pointed out that all theories are defective in that they disregard the fact that one at least of the media is
**dispersive**, and that it is probable that finite reflection would result at the interface of media of different**dispersive**powers, even in the case of waves for which the refractive indices are absolutely the same. - By introducing a
**dispersive**lens of flint the magnifying glass could be corrected for both chromatic and spherical aberrations. - To an achromatic collective lens, which is turned towards the object, a
**dispersive**lens is combined (this type to a certain extent belongs to the compound microscope). - By altering the distance of the collective and
**dispersive**members the magnification can be widely varied. - In the case of the
**dispersive**eyepiece, on the contrary, no sharply limited field can arise, but vignetting must occur.