Color CRT shadow mask and method of making same

Details Color CRT shadow mask and method of making same Color CRT shadow mask and method of making same

1979-04-03

1980-07-01

McQuade, John

Electric lamp and discharge devices

Cathode ray tube

Shadow mask, support or shield

29 2518, 313402, H01J 902

Patent

active

042108438

ABSTRACT:
This disclosure depicts an improved method of making a color CRT shadow mask. The improved method comprises providing a plurality of shadow mask blanks each with a pattern of apertures photoetched therein, which blanks have been cut from a foil of steel, precision cold-rolled to a full hard condition with a thickness of about 6-8 mils. The sheet is characterized by being composed of an interstitial free steel material. A stack of the blanks is subjected to a limited annealing operation, by being carried out at a relatively low maximum temperature and for a relatively brief period sufficient only to achieve recrystallization of the material without causing significant grain growth. The maximum temperature is below the temperature at which the blanks mutually adhere, and thus avoiding any handling-related folding or creasing of the blanks normally associated with attempts to separate blanks stuck together in conventional high temperature annealing operations. Each blank is clamped and drawn to form a dished shadow mask without the interposition of vibration or roller leveling operations and thereby avoids undesirable creasing, roller marking, denting, tearing or work hardening of the blank normally associated with these operations. The end product shadow mask, due to the use of said interstitial free steel material, has an aperture pattern of improved definition as a result of more uniform stretching of the mask blank.

REFERENCES:
patent: 3676914 (1972-07-01), Fiore
patent: 3693223 (1972-09-01), Kaplan
patent: 3909311 (1975-09-01), Yamada et al.
patent: 3909928 (1975-10-01), Sato et al.
patent: 3973964 (1976-08-01), Lange
patent: 3975198 (1976-08-01), Palac et al.
patent: 3983613 (1976-10-01), Palac et al.

Affiliated with

Also associated with

Rating

Color CRT shadow mask and method of making same does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Color CRT shadow mask and method of making same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Color CRT shadow mask and method of making same will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-300268