Abstract: A digital electrical signal Vin for transmission is supplied to a transistor Q12, a current compensation circuit 11, and a signal current source 13 to be band-compensated for generating a signal current I0. A predetermined current Id for a constant-current source 14 is subtracted from the signal current I0, and the result is an injection current Iin that drives an LED 15. The current Id is adjusted so that the injection current Iin becomes 0 at the low level. Thus, a signal-to-noise (S/N) ratio in waveform of light outputted from the LED 15 can be improved. Accordingly, the S/N ratio of the transmitted signal can be improved with band compensation.

Abstract: A discriminator capable of generating a multi-level signal with less restrictions is provided. In a discriminator D1, a wave-shaping circuit 3 shapes the waveform of one branched multi-level signal MS, according to a control signal CS from a control signal generator 10 so that a detector 4 that follows the wave-shaping circuit 3 can correctly detect a first reference level RL1. The detector 4 detects the first reference level RL1 from an output signal OS3 from the wave-shaping circuit 3. A reference level generator 5 generates a second reference level RL2 of the multi-level signal MS. A threshold generator 6 generates thresholds Th1, Th2, and Th3 as much as required according to the first and second reference levels RL1 and RL2. Comparators 82 to 84 compares the amplitude of the other branched multi-level signal MS with the thresholds Th1, Th2, and Th3. A control signal generator 10 generates a control signal CS according to the comparison results from the comparators 82 to 84.

Abstract: A group of semiconductor laser diodes 1 outputs fundamental-wave lights controlled so that each wavelength thereof is double the wavelength of a light for wavelength multiplexing transmission. The fundamental-wave lights are provided to a light receiver 2, and then to a group of wavelength conversion elements 3, wherein the fundamental-wave lights are converted into lights each having half the wavelength of each fundamental-wave light. The group of wavelength conversion elements 3 outputs lights including the converted lights each having half the wavelength of each fundamental-wave light and the fundamental-wave lights. The outputted lights are passed through a group of fundamental-wave optical eliminators 4 typified by an optical filter for passing the converted lights and eliminating the fundamental-wave lights, a guiding part 5, and then an optical multiplexer 6, and then guided to a transmission medium 7.

Abstract: Provided by the present invention are novel diguanamine derivatives, led by 2,5/2,6-bis(4,6-diamino-1,3,5-triazin-2-yl)-bicyclo?2.2.l!heptanes and 1,3/1,4-bis(4,6-diamino-1,3,5-triazin-2-yl)-cyclo-hexanes, and derivatives thereof, applications of these compounds in fields such as adhesives and paints, utilization of these compounds in flame-retarding, thermal stabilization and compatibilization methods of resins, thermosetting molding compositions and thermosetting expansion-molding compositions making use of these compounds, as well as polymeric microspheres also using these compounds. These compounds are expected to find wide spread industrial utility as various excellent properties can be obtained by using them.

Abstract: Provided by the present invention are novel diguanamine derivatives, led by 2,5/2,6-bis(4,6-diamino-1,3,5-triazin-2-yl)-bicyclo?2.2.1!heptanes and 1,3/1,4-bis(4,6-diamino-1,3,5-triazin-2-yl)-cyclohexanes, and derivatives thereof, applications of these compounds in fields such as adhesives and paints, utilization of these compounds in flame-retarding, thermal stabilization and compatibilization methods of resins, thermosetting molding compositions and thermosetting expansion-molding compositions making use of these compounds, as well as polymeric microspheres also using these compounds. These compounds are expected to find wide spread industrial utility as various excellent properties can be obtained by using them.

Abstract: Provided by the present invention are novel diguanamine derivatives, led by 2,5/2,6-bis(4,6-diamino-1,3,5-triazin-2-yl)-bicyclo[2.2.1]heptanes and 1,3/1,4-bis(4,6-diamino-1,3,5-triazin-2-yl)-cyclohexanes, and derivatives thereof, applications of these compounds in fields such as adhesives and paints, utilization of these compounds in flame-retarding, thermal stabilization and compatibilization methods of resins, thermosetting molding compositions and thermosetting expansion-molding compositions making use of these compounds, as well as polymeric microspheres also using these compounds. These compounds are expected to find wide spread industrial utility as various excellent properties can be obtained by using them.

Abstract: Provided by the present invention are novel diguanamine derivatives, led by 2,5/2,6-bis(4,6-diamino-1,3,5-triazin-2-yl)-bicyclo[2.2.1]heptanes and 1,3/1,4-bis(4,6-diamino-1,3,5-triazin-2-yl)-cyclohexanes, and derivatives thereof, applications of these compounds in fields such as adhesives and paints, utilization of these compounds in flame-retarding, thermal stabilization and compatibilization methods of resins, thermosetting molding compositions and thermosetting expansion-molding compositions making use of these compounds, as well as polymeric microspheres also using these compounds. These compounds are expected to find wide spread industrial utility as various excellent properties can be obtained by using them.

Abstract: A parallel signal transmission system for transmitting parallel signals from a transmission unit to a reception unit via an optical fiber, at a low cost without spoiling their quality. The transmission unit converts received parallel signals into serial signals frame by frame, by means of a frame sync signal, and further converts the serial signals into direct current equilibrium signals which are either CMI codes or DMI codes. At the same time, the direct current equilibrium signals are multiplexed with the frame sync signal in accordance with the code ruling violation in order to drive a laser diode having a 0.78 .mu.m wavelength and output intensity-modulated optical signals to the optical transmission path. As the optical transmission path, a plastic clad fiber is used whose core diameter is 200 .mu.m or larger in order to agree with the laser diode having a 0.78 .mu.m wavelength.

Abstract: Provided by the present invention are novel diguanamine derivatives, led by 2,5/2,6-bis(4,6-diamino-1,3,5-triazin-2-yl)-bicyclo[2.2.1]heptanes and 1,3/1,4-bis(4,6-diamino-1,3,5-triazin-2-yl)-cyclohexanes, and derivatives thereof, applications of these compounds in fields such as adhesives and paints, utilization of these compounds in flame-retarding, thermal stabilization and compatibilization methods of resins, thermosetting molding compositions and thermosetting expansion-molding compositions making use of these compounds, as well as polymeric microspheres also using these compounds. These compounds are expected to find wide spread industrial utility as various excellent properties can be obtained by using them.