It is known that reception of optical information in television is carried out by visual system which has limited resolution. This imperfection of visual system along with decrease of sensitivity of sight to perception of small elements of the image has the filtering effect concerning high-frequency components of fluctuation hindrances. Low-frequency hindrances are more noticeable, than high-frequency the same power. Weakening of visual perception of high-frequency components of hindrances, besides, happens in connection with ability of visual system to smooth emissions of hindrances and the lowered contrast sensitivity of sight in the presence of hindrances.
As a result the number of half tones (number of threshold gradation of a ) to Ai in TV the image decreases in comparison with number of at direct supervision of objects And In this regard also the identification of objects worsens.
uses of real red, green and blue of color kinescopes, spectral characteristics and which limit reproduction of the maximum coverage (range of the reproduced flowers which can be realized within three-component by TV of system);
For the accounting of this feature of sight enter concept of electric model of the resolution of an eye presented in the filter form which amplitude-frequency characteristic is approximated by so-called weight function of hindrances of D (f) (see drawing. This filter call weighing. According to the recommendation of MKKR in color TV the filter which characteristic of attenuation has an appearance is used:
In this section of an academic year project it is necessary to determine parameters and type of a hindrance which creates on the screen of the television receiver the stationary picture specified in the drawing Image of a Hindrance on the screen – set of motionless bright thin straight lines against a dark background. Parameters of decomposition of the television standard - 62550, k=1: We will accept time of reverse motion on a line (field) equal to zero.