. The principles of physics. Fig. 322. vantages derivedare as follows: 1. The combination diminishes spherical aberration and therebyincreases the flatness of the field. The images o 6 and a b (Fig. 323)are in reality curved in consequence of the spherical aberration COMPOUND MICROSCOPE. 425 caused by the objective. The effect of the field lens is to correctthis curvature in a measure. 2. The combination increases the field of view, so that a largerarea of the object is made visible at the same view. 3. The combination diminishes chromatic aberration. All microscopes, however, should be furnis
. The principles of physics. Fig. 322. vantages derivedare as follows: 1. The combination diminishes spherical aberration and therebyincreases the flatness of the field. The images o 6 and a b (Fig. 323)are in reality curved in consequence of the spherical aberration COMPOUND MICROSCOPE. 425 caused by the objective. The effect of the field lens is to correctthis curvature in a measure. 2. The combination increases the field of view, so that a largerarea of the object is made visible at the same view. 3. The combination diminishes chromatic aberration. All microscopes, however, should be furnished vfith an achro-. FlG. 323. matic objective. This consists of two to four achromatic lenses,(the achromatic triplet, the most common form, is represented onan enlarged scale at L in Fig. 323), combined so as to act as asingle lens of short focus. By the use of several lenses, the aber-rations can be better corrected than with a single lens. 426 ETHBE DYNAMICS.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectphysics, bookyear1895
