A resistance circuit included in a semiconductor apparatus, which is formed of a plurality of thin film metal resistors connected in series, capable of achieving a precise resistance adjustment over a wide range by disconnecting or changing the resistors by laser beam irradiation. With three thin film metal resistors R1, R2, and R3 connected in series, for example, each having resistance adjustable ranges .DELTA.R1, .DELTA.R2, and .DELTA.R3, resistance adjustment accuracies R1_step, R2_step, and R3_step, and the total resistance adjustable range .DELTA.R0 specified by the relation .DELTA.R0=.DELTA.R1+.DELTA.R2+.DELTA.R3, the resistance circuit is formed to satisfy relational expressions, R1_step.ltoreq..DELTA.R2, R2_step.ltoreq..DELTA.R3, and R3_step.ltoreq.0.001.times..DELTA.R0

 
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> Optical information recording method and apparatus for multiple recording layer medium

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