Instruction Guide: Elementary Optics and Applications to Fire Control InstrumentsU.S. Government Printing Office, 1945 - 211 σελίδες |
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Σελίδα 7
... optical elements , it will retrace its path through the elements if the light were to enter the optical system from the other end . This is true , no matter how many reflections and refractions the light has under- gone . 4. SPEED OF ...
... optical elements , it will retrace its path through the elements if the light were to enter the optical system from the other end . This is true , no matter how many reflections and refractions the light has under- gone . 4. SPEED OF ...
Σελίδα 25
... optical elements , virtual images and real images . ( 1 ) VIRTUAL IMAGES . A virtual image is so called because it has no objective or real existence . It exists only in the mind and cannot be thrown upon a screen because it is apparent ...
... optical elements , virtual images and real images . ( 1 ) VIRTUAL IMAGES . A virtual image is so called because it has no objective or real existence . It exists only in the mind and cannot be thrown upon a screen because it is apparent ...
Σελίδα 26
... eye and the camera form real images . The real image formed by a camera can be seen on the ground glass ( fig . 38 ) . b . Erect , Inverted , Normal , and Reverted Images . When an image is reflected or refracted by optical elements , the ...
... eye and the camera form real images . The real image formed by a camera can be seen on the ground glass ( fig . 38 ) . b . Erect , Inverted , Normal , and Reverted Images . When an image is reflected or refracted by optical elements , the ...
Σελίδα 27
... Optical Elements a . When the image of an object is seen in a mirror , it appears to be located at a distance behind the reflecting surface equal to the distance of the object from the front of the mirror . The image is erect and ...
... Optical Elements a . When the image of an object is seen in a mirror , it appears to be located at a distance behind the reflecting surface equal to the distance of the object from the front of the mirror . The image is erect and ...
Σελίδα 39
... optical elements . While this loss may be as great as 75 percent , every effort is made to reduce the loss to a minimum . A contributing factor in brightness of image is an objective lens aperture ( usable portion ) large enough to ...
... optical elements . While this loss may be as great as 75 percent , every effort is made to reduce the loss to a minimum . A contributing factor in brightness of image is an objective lens aperture ( usable portion ) large enough to ...
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