8.3: A High‐Defiection‐Sensitivity CDT with Rectangular Yoke

Abstract

A new system of CDT(Color Display Tube) yoke has been developed. In this system, not only the bulb cone and the horizontal and vertical coils of DY(Deflection Yoke), but also its core are transformed from a round shape to a substantially rectangular shape at the screen side of the DY. Owing to the reduction of the deflection current and the coil inductance, the deflection power has been reduced by 23% in comparison with a conventional round DY. and also, the 2M pixels display capability with 110kHz scanning frequency has been subsequently accomplished.

High‐deflection‐sensitivity CRTs with filled yoke

“…At a given line current i(θ), filling the DY leads to an enhanced field, and thus to an increase in line inductance L. This inductance is defined as L = Φ/I, where Φ is the total magnetic flux through the coil at a drive current I. The distribution of windings in the coil is proportional to the current distribution in the first quadrant (0 < θ < π/2) 10 : (6) where N w (θ) is the number of windings at angular position θ characterized by the Fourier coefficients i n /I which repre-sent the wire distribution. The magnetic flux through one turn between θ 0 and πθ 0 is given by (7) Here, B r (R 1 , θ) = -µ 0 (∂Ψ/∂r) is the radial component of the magnetic induction B at the coil.…”

“…Techniques to improve the DY sensitivity, which is inversely proportional to LI 2 , are anode voltage reduction, 4 mini-neck, 5 or rectangular cone (RAC). 6 At the AD/IDW '01 conference, 7 we presented a complementary technique to gain another 15-25% in deflection sensitivity. 8,9 This gain was obtained by filling all void spaces between the ferrite core and the line deflection coils with a material with a relative magnetic permeability of about 10.…”

36.2: Transposed Scanning: The Way to Realize Super‐Slim CRTs

“…For transposed scan it is higher. This implies that for wide-screen CRTs the relative gain in sensitivity when going from a rotationally symmetric glass/coil design to a rectangular design (RAC) [4] is larger for transposed scan than it is for normal scan. From our calculations we find a gain in line coil sensitivity of 12% for normal scan and a gain of 31% for transposed scan (cf.…”

Recent Advances in Deflection Yoke Design

“…Sony focused on convergence improvement with digital convergence correction circuitry (8). Toshiba succeeded in minimizing stored energy by introducing CRT with retangular neck and deflection yoke and ferrite core of retangular cross-sections (9). Hitachi emphasized shallower cabinet depth with the 100° deflection angle in their 17" monitor (10).…”