Dalton H. Pritchard v. Donald Richman

360 F.2d 236, 53 C.C.P.A. 1322
CourtCourt of Customs and Patent Appeals
DecidedJuly 28, 1966
DocketPatent Appeal 7597
StatusPublished

This text of 360 F.2d 236 (Dalton H. Pritchard v. Donald Richman) is published on Counsel Stack Legal Research, covering Court of Customs and Patent Appeals primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Dalton H. Pritchard v. Donald Richman, 360 F.2d 236, 53 C.C.P.A. 1322 (ccpa 1966).

Opinion

ALMOND, Judge.

This appeal is from the decision of the Board of Patent Interferences awarding priority of invention as to counts 1 through 6, the only remaining counts of interference No. 90,260, to Donald Rich-man, the senior party.

Richman is involved in the interference on his application serial No. 359,784 filed June 5, 1953 and assigned to Hazel-tine Research, Inc. Dalton H. Pritchard, the junior party, is involved on the basis of patent No. 2,830,112, issued April 8, 1958 on an application filed May 26, 1954 and assigned to Radio Corporation of America (RCA). Counts 1, 2, 3, 4, 5 and 6 correspond to claims 1, 9, 10, 11, 12 and 13, respectively, of the Pritchard patent.

Two issues are raised by the appeal. The first is whether priority testimony introduced by Pritchard with respect to counts 1, 2, 4, 5 and 6 fails, as ruled by the board to prove completion of the invention of those counts prior to Rich-man’s filing date. The other issue is whether the board erred in agreeing with the examiner that Richman’s application discloses the subject matter of count 3. 1

The invention relates to circuitry for use in color television receivers. Considered broadly, the circuitry demodulates, or detects, two color signals from the received color signal and then combines them to provide three color signals having different characteristics which are suitable for use in producing the color picture.

Counts 1 and 3 are representative:

1. In a color-television receiver, said color-television receiver adapted to receive a color-television signal, said color-television signal including a color subcarrier containing a plurality of color signals, each of said color signals corresponding to a predetermined signal phase, matrix means adapted to accept a first plurality of signals corresponding to a first group of predetermined signal phases in said color subcarrier to yield a second plurality of signals corresponding to a second group of predetermined signal phases, said matrix means comprising in combination, a plurality of transmission networks, each of said transmission networks having a first control electrode, a second control electrode and an output electrode, a mutual impedance coupled to the first control electrode of each of said transmission networks to cause any signal developed in one transmission network to drive each of the other transmission networks, means for coupling each of said *238 plurality of signals to the second control electrode of a prescribed group of said transmission networks corresponding in number to said first plurality of signals, means for utilizing said mutual impedance to produce signal addition of determinable amplitudes and polarities of said first plurality of signals at the output terminals of each of said transmission networks to cause each signal of said second plurality of signals to appear at the output terminal of one of said plurality of transmission networks.
3. In a color-television receiver adapted to receive at least a chromi-nance signal, the combination of demodulator means to demodulate a first and second color-difference signal from said chrominance signal corresponding to information at determinable angles of said chrominance signal, a trio of electron stream devices each having output circuits and coupled to cause modulation introduced in one electron stream to provide corresponding modulations in the other electron stream devices, means for modulating the electron streams of a pair of said trio with said first and second color-difference signals respectively, means for causing signal addition in each of said trio due to said coupling to develop each of a trio of color-difference signals corresponding to angles of said chrominance signal other than the angles corresponding to said first and second color-difference signals in each output circuit.

The record shows that although red, blue and green color signals are derived from the scene being viewed in color television, they are not transmitted as they come from the color cameras. Instead, they are compounded to produce a luminance signal and a chrominance modulated color subcarrier signal, and those signals are transmitted to the receiver. The luminance signal Y, although it is made up of predetermined proportions of the original red, blue and green signals, is actually representative of the brightness rather than color and is used to produce the black and white picture in a black and white receiver. The chro-minance subcarrier is modulated in phase and amplitude with two color difference signals representative of the hue and saturation of the color. Theoretically, those color difference signals could be red and blue color difference signals, R-Y and B-Y, which after being demodulated from the chrominance subcarrier signal in the receiver can be added or matrixed to provide additionally a green color difference signal, G-Y. The red, blue and green color difference signals, which Pritchard describes as representing information relating to the corresponding color component “minus information as to the ‘luminance’ or brightness,” are used to produce the color picture on a tri-color picture tube.

The specifications of both parties describe a system in which the chrominance subcarrier signal, instead of being modulated by red and blue color difference signals, is modulated by signals representative of color difference along orange-cyan and green-purple axes which are displaced 90 degrees in phase and are designated I and Q signals, respectively. 2

The parties demodulate the received chrominance subcarrier signal to obtain two color difference signals other than the red and blue color difference signals 3 and then combine or matrix those two signals to obtain the three color difference signals R-Y, B-Y and G-Y.

As noted by the board, the crux of the common invention of the parties lies in the matrixing. Both parties are con *239 cerned with simplification of circuitry for producing red, blue and green color difference signals from two demodulated color difference signals of different phase position than the red, blue and green signals. Both parties disclose a circuit including three electron tubes of the triode type with a common resistor in the circuit from cathode to ground with each of the two demodulated signals impressed on the control electrode of one of the two triodes and with the control electrode of the third triode connected directly to ground. The outputs taken from the anodes of the three triodes represent the red, blue and green color difference signals respectively. Those output signals are obtained through intermixing the two input signals in three different ways as a result of their each contributing to the voltage drop across the cathode resistor common to all three cathode circuits. The effect is that of vectorially adding the two input signals in the proper polarities and magnitudes to provide the red, blue and green color difference signals. Correct proportioning is achieved through selection of the relative impedances in the circuits of the triodes. Although the Pritchard and Richman circuits operate on the same principle, they differ in detail due to the difference in phasing of the input signals.

Both parties took testimony.

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Cite This Page — Counsel Stack

Bluebook (online)
360 F.2d 236, 53 C.C.P.A. 1322, Counsel Stack Legal Research, https://law.counselstack.com/opinion/dalton-h-pritchard-v-donald-richman-ccpa-1966.