focal length, viewfinder, collimator, magnification, chromatic aberration, eyepiece, collimation, zoom lens, emissivity, spherical aberration, iris diaphragm, parallax, lens, arcsecond, pentaprism, diffraction, vignetting, autofocus, camera lens, brightness, monochromator, reticle, luminance, telephoto, photodiode, micrometer, diopter, photodetector, passband, photometry, photodiodes, convex lens, fovea, workpiece, wavefront, absorption coefficient, flashgun, chroma, detents, optics, photometer, transmittance, capacitances, imager, colorimetry, nosepiece, pinhole, waveguide, transmissivity, illuminance, platen, phototransistor, image intensifier, illuminator, toroidal, azimuthal, convex, collet, circular polarization, coronagraph, fundus, pyrometer, bevel, femtosecond, diameters, directivity, capsulotomy, mev, retroreflector, fisheye, pixels, defocus, photocell, lamella, galvo, concentricity, toroid, parabolic reflector, zoom, gearset, kev, baseplate, halftone, chamfer, micrometre, angstroms, conductance, photomultiplier, refractive index, refraction, reticule, leica, inductance, dipole moment, infrared, galvanometer, polarimeter, countersunk, nozzle, submicron, laparoscope, etalon, apertures, opening, slit, openings, orifice, fin, inlet, pore, cavity, notches, triangular, angle, fins, orifices, protuberance, siphon, crosssection, ft., lateral, area, scanning, bistatic, holographic, multichannel, multielement, twodimensional, dimensional, multispectral, polarization, saturation, scan, spacing, antenna, bidimensional, confocal, element, multiband

embouchure, micropyle, mouthpiece, pore, pupil, stoma

abbe condenser, camera obscura, cassegrainian telescope, diaphragm, dilatation, dilation, embouchure, free-reed, gregorian telescope, mouthpiece, opening, orifice, peep sight, porta, portrait lens, pupil, scorpion shell, shouldered arch, stigma, stop, whistle, whistling

camera, photographic camera, scope, telescope

hole, opening, regulator