Who invented PAL?

[yagosaga]

Hi folks,

Does somebody here know that the PAL color system was not invented by Walter Bruch but by the American engineer Bernard Loughlin. Loughlin invented the "Color Phase Alternation" in 1951. The phase of the color carrier was switched every new line or frame, and the phase shift was annihilated in the eye of the beholder.

In case of large phase shifts, a strong flicker appeared on the screen (with frame swichting) or a jalousie effect with line switching. Loughlin’s patent #928474 was accepted 1952 in Germany. The patent expired in 1960. The French engineer Gérard Melchior got a French PAL patent #889835 in 1962. Walter Bruch’s attempts to get a PAL patent were unsuccessful due to the former American and French PAL patents.

Meanwhile, SECAM was established in France, and Bruch took the idea of an acoustic 64 uS delay line from SECAM, and integrated this idea in Loughlin’s invention. Bruch run another attempt to get a patent for the PAL color system. But the patent office accepted only a patent for using a delay line in the color television receiver. More curious: Bruch’s unique color television patent was not a PAL patent, but an NTSC-patent. Bruch‘s patent DE 1252731 is called "Color television receiver for a color-reliable NTSC-system". So, Bruch, the "father of the PAL system" did not invented PAL. He only invented a color-reliable NTSC receiver. But the true merits of inventing PAL belongs to an American. In 1951, Loughlin mentioned that a hue control for NTSC is easier to install than the electronics of a "Color Phase Alternation". And without SECAM and the use of the delay line in the SECAM decoder, the PAL system would not developed. So, PAL is a child of NTSC and SECAM.

When PAL color television was introduced in Germany, General Electrics and SONY sold color tv receivers according to Loughlin's patent (so called "Simple PAL receivers" without the delay line), and they had not to pay any licence fees to Bruch or to Telefunken. Loughlin's Simple PAL receivers have stunning color pictures. Together with SONYs trinitron CRT, they had a better color reproduction than Bruch's standard PAL receivers.

Kind regards,
Eckhard