Heat-sensitive recording head with minimum number of switching diodes

A heat-sensitive recording head comprising:

• an insulating substrate;
• an array of heat generating elements;
• a plurality of leads alternately arranged on both sides of said array of heat generating elements on said insulating substrate with said heat generating elements interposed between said leads;
• a plurality of lead wires connected directly to predetermined ones of said leads, said lead wires being arranged in matrix wiring form including a plurality of common lead terminals with predetermined ones of said lead wires on a first side of said array being coupled directly to each of said common lead terminals and further including a plurality of individual lead terminals with predetermined ones of said lead wires on a second side of said array being coupled directly to each of said individual lead terminals, said lead wires coupled to said common lead terminals being coupled to said leads in blocks with two lead wires provided for each of said blocks, each of said lead wires being coupled to leads coupled to alternate ones of said heating elements;
• and
• wherein, with the number of blocks being represented by n, the number of individual lead terminals being represented by m, the average value of the resistances of said heat generating elements being represented by r, and the maximum variation of said resistances being represented by .+-..DELTA.r, said values n, m, .DELTA.r and r are set to satisfy:
• ##EQU34## where m>1 and .DELTA.r<r.

A heat-sensitive recording head comprising:

• an insulating substrate;
• an array of heat generating elements;
• a plurality of leads alternately arranged on both sides of said array of heat generating elements on said insulating substrate with said heat generating elements interposed between said leads;
• a plurality of lead wires connected to predetermined ones of said leads, a plurality of common lead terminals, and a plurality of individual lead terminals, said lead wires being arranged in matrix wiring form, predetermined ones of said lead wires on a first side of array being coupled directly to corresponding ones of said common lead terminals, said lead wires coupled to said common lead terminals being coupled directly to said leads in blocks with two lead wires provided for each of said blocks, each of said lead wires coupled to said common lead terminals being coupled directly to leads coupled to alternate ones of said heating elements, predetermined ones of said lead wires on a second side of said array being coupled between corresponding ones of said individual lead terminals and said leads on said second side of said array;
• and
• wherein, with the average value of the resistances of said heat generating elements being represented by r and the maximum variation of said resistances being represented by .+-..DELTA.r, said values r and .DELTA. are set so as to satisfy:
• r>.DELTA.r.