Abstract: A nonlinear optical dye includes a compound represented by the general formula (1) below. In the above general formula (1), each of X1, X2, X3 and X4 independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 6, a halogen atom, a hydroxyl group, a nitro group, a cyano group, or a methylsulfonyl group. In the present invention, it is preferred that each of X1, X2, X3 and X4 independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 6, or a halogen atom. In the present invention, it is also preferred that the nonlinear optical dye has a dipole moment of 2.1 D or less and a maximum absorption wavelength within a range of 315 to 360 nm.

Abstract: A nonlinear optical dye includes a compound represented by the general formula (1) below. In the above general formula (1), each of X1, X2, X3 and X4 independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 6, a halogen atom, a hydroxyl group, a nitro group, a cyano group, or a methylsulfonyl group. In the present invention, it is preferred that each of X1, X2, X3 and X4 independently represents a hydrogen atom, an alkyl group having a carbon number of 1 to 6, or a halogen atom. In the present invention, it is also preferred that the nonlinear optical dye has a dipole moment of 2.1 D or less and a maximum absorption wavelength within a range of 315 to 360 nm.

Abstract: A differential amplifier includes an input differential pair constituted by differential pair transistors whose common emitter is current-biased by a negative voltage source through a constant current source. An active load is formed by interconnecting through resistors input and output of a first and second current mirror circuit whose emitters serve as positive voltage sources. A collector output of each of the input differential pair is connected to each of the outputs of the first and second current mirror circuits. An output current amplifying stage comprises three emitter-grounded current amplifying stages whose emitters serve as positive voltage sources. The first current amplifying stage includes a capacity provided between the base and collector thereof and connected to one of current mirror outputs of the active load at the base thereof. The second and third current amplifying stages are connected to the other current mirror output of the active load at a common base.