condensing lens

A curved reflector redirects light that would otherwise be wasted toward the condensing lens.

A flat piece of heat-absorbing glass is often placed in the light path between the condensing lens and the slide, to avoid damaging the latter.

Diaphragm - an iris located just below the condensing lenses which restricts the amount of light entering the condenser.

A condenser enlarger consists of a light source, a condensing lens, a holder for the negative and a projecting lens.

Squat, huge, and heavy, it resembled somewhat an overgrown machine rifle but one possessing a thick, short telescope, with several opaque condensing lenses and parabolic reflectors.

In figure B, the emitted beam has been made convergent by adjusting the sleeve such that the source (S) is placed outside the focal point of the condensing lens.

In appearance it is somewhat different; indeed, it is in two parts, the one containing the lighting arrangements and condensing lens, and the other embracing the mechanism and objective lens.

Condensing lens: A divergent beam from the filament source is refracted by a plus condensing lens (typically approximately 50 D) before it is reflected by the mirror.

Such improvements include the provision of a sub-stage condensing lens, for increasing the intensity of reflected light from a candle or lamp, and a sub-stage mirror with one plane and one convex surface.