| John Hutton Balfour - Science - 1851 - 642 pages
...is called Hnyghen'?, and consists of two plano-convex lenses with their plane sides toward the eyt, **and placed at a distance apart equal to half the sum of their focal lengths, with a** diaphragm placed midway between the lenses. In this eye-piece, the leanext the eye is called the eye-glass,... | |
| Jabez Hogg - Microscopes - 1854 - 440 pages
...lenses, with their plane sides towards the eye, and placed at a distance apart equal to half the sum at **their focal lengths, with a stop or diaphragm placed...of the value of his eye-piece ; it was reserved for** Boscovicb. to point out that he had, by this important arrangement, accidentally corrected a great... | |
| John King - Microscope and microscopy - 1859 - 308 pages
...increasing the field of view. It consists of two plano-convex lenses, with their plane sides toward **the eye, and placed at a distance apart equal to half...lengths, with a stop or diaphragm placed midway between** these two lenses. Hnyghens was not aware of the value of his eye-piece ; it was reserved for Boscovich... | |
| Jabez Hogg - Science - 1861 - 621 pages
...Huyghens for telescopes, with no other view than that of diminishing the spherical aberration by p/oducing **the refractions at two glasses instead of one, and...diaphragm placed midway between the lenses. Huyghens** TO not aware of the value of his eye-piece ; it was reserved for Boscovich to point out that he had,... | |
| John Hutton Balfour - 1863
...also, must be so formed as to be free from error. That used is called Huyghens', and consists of two pL **lenses with their plane sides towards the eye, and...equal to half the sum of their focal lengths, with a** diaphragm inserted midway between the lenses. In this eye-piece, the lens next the eye u called the... | |
| Medicine - 1877
...lenses, with their plane sides next the eye, whose focal lengths are as 3 to 1, and which are placed **a distance apart equal to half the sum of their focal lengths.** This is, to be sure, an old formula, but is not used so far as we are aware, by any modern maker. The... | |
| Medicine - 1877
...lenses, with their plane sides next the eye, whose focal lengths are as 3 to 1, and which are placed **a distance apart equal to half the sum of their focal lengths.** This is, to be sure, an old formula, but is not used so far as we are aware, by any modern maker. The... | |
| Microscopy - 1885
...produce a fair combination." Two plano-convex lenses with foci 2 : 1 placed with planes to object and **at a distance apart equal to half the sum of their focal lengths** — the shorter focus lens being a thick one. With perfectly central light the definition of thin objects... | |
| Frank Crisp - 1885
...produce a fair combination." Two plano-convex lenses with foci H :1 placed with planes to object and **at a distance apart equal to half the sum of their focal lengths** —the shorter focus lens being a thick one. With perfectly central light the definition of thin objects... | |
| Edward Leamington Nichols - 1903
...1680. It consists of two lenses of similar glass, the respective focal lengths are as 3:1, and they are **placed at a distance apart equal to half the sum of their** respective focal lengths. This doublet is partially eye achromatic,* and it has a end very wide flat... | |
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