Instruction Guide: Elementary Optics and Applications to Fire Control InstrumentsU.S. Government Printing Office, 1945 - 211 σελίδες |
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Σελίδα 8
... observer . Other methods , employing the reflections from rotating mirrors and prisms , have since been used to establish the speed of light to an exactness beyond that required for practical usage . e . The speed of light is accepted ...
... observer . Other methods , employing the reflections from rotating mirrors and prisms , have since been used to establish the speed of light to an exactness beyond that required for practical usage . e . The speed of light is accepted ...
Σελίδα 25
... to the eyes of the observer . A familiar example is the virtual image formed by a mirror . The image of the person looking into the mirror appears Properties of Light RA PD 30244 RA PD 30245 to 25 TM 9-2601 Pars . 18-21.
... to the eyes of the observer . A familiar example is the virtual image formed by a mirror . The image of the person looking into the mirror appears Properties of Light RA PD 30244 RA PD 30245 to 25 TM 9-2601 Pars . 18-21.
Σελίδα 27
... observer to be located behind the mirror and on the other side of the room from which it actually is . The observer sees along the path of the reflected ray to the point where the incident ray is reflected by the mirror . His line of ...
... observer to be located behind the mirror and on the other side of the room from which it actually is . The observer sees along the path of the reflected ray to the point where the incident ray is reflected by the mirror . His line of ...
Σελίδα 31
... observer . Common examples are the reading glass and microscope . In a fire control instrument , magnification , by making targets appear larger , makes them appear closer . b . Minification is the apparent reduction in the size of the ...
... observer . Common examples are the reading glass and microscope . In a fire control instrument , magnification , by making targets appear larger , makes them appear closer . b . Minification is the apparent reduction in the size of the ...
Σελίδα 34
... observer looks at the object , for example , a portion of a printed page , through a reading glass held close to the type , the printed letters appear larger than they actually are . As he moves the glass away from the type , each ...
... observer looks at the object , for example , a portion of a printed page , through a reading glass held close to the type , the printed letters appear larger than they actually are . As he moves the glass away from the type , each ...
Συχνά εμφανιζόμενοι όροι και φράσεις
ABBE PRISM achromatic adjustment Amici prism angle of incidence astigmatism axis azimuth binocular chromatic aberration Coated Optics collective lens color compound lens concave Construction Features convergent lens convex critical angle crown glass curvature deviation diopter divergent lens Elbow Telescope ERECTOR exit pupil eyepiece field of view Figure filters Fire Control Instruments flint glass focal length focal plane focal point focusing Glossary height finder horizontal incident ray index of refraction inverted lens erecting system lenses light rays line of sight magnification medium mils mirror mounted normal objective prism observer Optical Components Optical Diagram optical elements optical instrument optical system Panoramic Telescope parallel path of light penta prism periscope point of light PORRO PRISM prism erecting system Properties of Light RA PD range finder rays of light real image reflected ray reflecting surface Representative Fire Control reticle retina right angles spherical aberration stereoscopic target vision wave length yards
Δημοφιλή αποσπάσματα
Σελίδα 181 - When a ray of light passes from one medium to another, it is refracted so that the ratio of the sine of the angle of incidence to the sine of the angle of refraction is equal to the ratio of the velocities in the two media.
Σελίδα 6 - BY ORDER OF THE SECRETARY OF WAR: GC MARSHALL, Chief of Staff. OFFICIAL: JA ULIO, Major General, The Adjutant General.
Σελίδα 12 - ... which struck the water, that is to say the angle of reflection will be equal to the angle of incidence.
Σελίδα 188 - Usually a thin coating of silver or aluminum on glass constitutes the actual reflecting surface. When this surface is applied to the front face of the glass, the mirror is termed a front surface mirror.
Σελίδα 186 - The magnifying power of the telescope is equal to the quotient of the focal length of the objective divided by the focal length of the ocular.
Σελίδα 148 - Each degree is divided into 60 parts called minutes, and each minute into 60 parts called seconds.
Σελίδα 89 - A filter is usually of special glass, gelatin, or plastic optical parts with plane parallel surfaces that are placed in the path of light through the optical system of an instrument to selectively absorb certain wavelengths of light, reduce glare, or reduce light intensity. Colored, ultraviolet, neutral density, and polarizing filters are in common use. Filters may be separate elements or integral devices mounted so that they can be placed in or out of position in...
Σελίδα 16 - The plane which contains the incident and reflected rays and the normal to the surface is called the plane of incidence, the angle between the incident ray and the normal is the angle of incidence...
Σελίδα 182 - The index of refraction expressed in tables is the absolute index, that is, vacuum to substance at a certain temperature, with light of a certain wavelength. Examples, vacuum, 1.000; air, 1.000292; water, 1.333; ordinary crown glass, 1.516. Since the index of air is very close to that of vacuum, the two are often used interchangeably.
Σελίδα 181 - Descartes notices — and this seems to be the first step in the reduction — that "the determination of this [anaclastic] line depends on the relation between the angle of incidence and the angle of refraction