Patent ID: 7151511

Claim:
A light-emitting device having a plurality of pixels, each of said plurality of pixels comprising: a source signal line, n (n is a natural number, 2≦n) writing gate signal lines, n reading gate signal lines, n writing transistors, n reading transistors, n×m memory circuits for storing n-bit digital image signals for m frames (m is a natural number, 1≦m), n writing memory circuit selection portions, n reading memory circuit selection portions, a current supply line, an EL driving transistor, and an EL element, wherein: gate electrodes of said n writing transistors are electrically connected to different ones of said n writing gate signal lines, one of a source region and a drain region of each of said n writing transistors is electrically connected to said source signal line, and the other of the source region and the drain region of each of said n writing transistors is electrically connected to signal input portions of said n writing memory circuit selection portions; each of said n writing memory circuit selection portions includes m signal output portions, with said m signal output portions being respectively and electrically connected to signal input portions of different memory circuits; each of said n reading memory circuit selection portions includes m signal input portions, with said m signal input portions being respectively and electrically connected to signal output portions of said different memory circuits; and gate electrodes of said n reading transistors are electrically connected to different ones of said n reading gate signal lines, one of a source region and a drain region of each of said n reading transistors is electrically connected to different signal output portions of said n reading memory circuit selection portions, the other of the source region and the drain region of each of said n reading transistors is electrically connected to a gate electrode of said EL driving transistor, one of a source region and a drain region of said EL driving transistor is electrically connected to said current supply line, and the other of the source region and the drain region of said EL driving transistor is electrically connected to one electrode of said EL element.