In the i-th shadow mask
, the proposed method obtains a proper threshold value [t.sup.*.sub.i] that maximizes the discrete difference of [f.sub.i] (t) in a threshold level step At as follows:
In order to obtain a shadow mask
, the gray thresh function based on Otsu's method , which chooses the threshold to minimize the intraclass variance of the black and white pixels, is used to convert an intensity image into a binary image.
According to the results of the measurements performed in the present study, it can be concluded that proper shadow mask
of LDR sensor will increase the accuracy and reduce the tracking time of tracking sun's radiation.
"By incorporating the ViewSonic PerfectFlat technology with a slot mask design, the GF775 offers the benefits of both shadow mask
and aperture grille tubes to produce brighter, sharper images with superior focus and vivid color," said Sally Wang, Product Line Manager at ViewSonic.
Utilizing advanced flat-square Invar shadow mask
technology, Hitachi's design reduces both the horizontal and vertical dot pitches to one of the lowest in the industry.
To help improve picture quality all new models have darker screens, INVAR shadow mask
and several higher-end models now have more power in the tube for a brighter picture.
* There is a parallax effect when sighting through the outer test zones of a large mask because it lies a fraction of an inch in front of the TV tube's shadow mask
. This forces me to shift my head from side to side when testing these zones, so that I am always looking squarely through each opening.
NEC's Invar Shadow Mask
improves contrast and makes each monitor up to 20 percent brighter than conventional CRTs without sacrificing focus quality.
According the definitions above, the shape of the shadow mask
could be derived easily by the following routine: first, calculate the normalized thickness distribution vector ([T.sup.original]), and then the shadow portion vector (T) could be obtained by substracting ([T.sub.original]) on the desired thickness distribution ([T.sub.target]); second, calculate values of each element in [S] by calculating values of [T.sub.j] under some different values of [[theta].sub.i] and liner fitting the relation of [[theta].sub.i] versus [T.sub.j], and then [S.sub.ij] equals the slope of the fitting result; last, derive mask shape parameters by solving (2) reversely; that is,
The p1450 19-inch CRT monitor utilizes a new Invar shadow mask
flat tube to reduce reflection while maintaining sharp text quality.
Complementary metal shadow masks
(Towne Technologies) were used to fabricate the thermopile structure.