A hinge for an orthopedic splint has two plates hinged for pivotal movement relative to each other and a detent engageable for locking the plates at a selected angle to each other, and a spring urging the detent into engagement. One embodiment comprises a memory system having multiple cache memories that have increasing data latencies and amounts of storage. Information is recorded on the optical recording medium by irradiating an optical spot on the optical recording medium. The first reset period includes a sub-period in which resetting is performed by a highest reset voltage of the plurality of reset voltages, and the second reset period includes a sub-period in which resetting is performed by the first reset voltage, wherein these two sub-periods are substantially equal in length.