Mitsubishi Denki Kabushiki Kaisha

Other

Mitsubishi Lighting Fixture Co., Ltd.

Isamu Ogawa

Koji Shibata

Hiroaki Nishikawa

Jun Bunya

Satoshi Nagai

Takeshi Arai

Kenichiro Nishi

Kentaro Eguchi

Kazutaka Shimizu

Kenji Hamazaki

Kazuhiko Tsugita

Osamu Takahashi

Osamu Ishikawa

Tetsuya Kobayashi

Kouji Shibata

Takenori Kawamata

Tetuya Kobayashi

Isao Masatika

Tadashi Maeda

Moriaki Okuda

Naoki Wada

Yasunori Ieki

Fumio Yoda

The discharge lamp lighting apparatus includes: a direct current power supply E; switching elements Q and Q for switching a direct current supplied from the direct current power supply E so as to generate a high frequency current; a discharge lamp load circuit LAC which is constructed in a manner that a discharge lamp LA and a coupling capacitor C are connected in series, and the discharge lamp LA is lit by a high frequency current generated by the switching elements Q and Q ; a switching element control circuit IC for controlling the switching elements Q and Q . The discharge lamp lighting apparatus is further provided with a protective circuit NP which distinguishes a fault of the discharge lamp LA by detecting a voltage generated in the coupling capacitor C , and outputs a control signal to the switching element control circuit IC

Discharge lamp lighting apparatus

A handwriting verification device includes: a normalizing section for normalizing an inputted handwriting which has been subjected to sampling at regular intervals; a registered handwriting dictionary in which registered handwriting is accommodated; a correspondence making section for making the inputted handwriting, which has been normalized in accordance with the sampling points in the sampling, correspond to the registered handwriting, so that a portion of the inputted handwriting and a portion of the registered hand writing, which coincide with each other, can be made to correspond to each other; a segment making section for making the inputted handwriting and the registered handwriting to be a segment by allotting an interval between at least two continuous sampling points as a segment in accordance with the result of making correspondence; a characteristic extracting section for extracting the characteristics of the inputted handwriting and the registered handwriting for each segment; and a handwriting verification section for verification the inputted handwriting with the registered handwriting using the characteristic of each segment.

Handwriting verification device

A discharge lamp lighting device in which dim control can be performed for a discharge lamp continuously and stably in a wide range, and which is simple in circuit configuration and low in price. The discharge lamp lighting device comprises: an inverter (IV) for turning on/off switching elements (Q,, Q,) by an oscillation output signal of an IV control integrated circuit (IC,) to thereby invert a voltage of a DC power supply (E) into high-frequency electric power, a discharge lamp (LA) capable of being lighted by the high-frequency electric power from the inverter (IV), a feedback circuit (FB) having delay time T (unit: second) expressed by 1/f&lE;T&lE;1/10,000 when the frequency of the high-frequency electric power is f, the feedback circuit (FB) including a reference value setting means (R,) for setting a reference value, the feedback circuit outputting a voltage for controlling the IV control integrated circuit (IC,) to make the high-frequency electric power equal to the reference value.

Discharge lamp lighting device

A current flowing through a discharge lamp 4 is detected by a current detecting circuit 5, and the detected current is outputted as a lamp current signal A to a feedback control circuit 7 where a difference between the lamp current signal A and the dimming control signal B is obtained and amplified, and then a simplified signal D is outputted to an adder 12 which adds the amplified signal D to the dimming control signal B to constitute a control signal E. The control signal is fed back to a high frequency power supply 2. When a comparing circuit 15 detects that the light level of the dimming control signal B with respect to the full light becomes higher than or equal to 40% to 60%, the feedback circuit is disconnected by operating a switch 13 provided between an error amplifying circuit 9 and an adder 12 to stop the feedback control.

Discharge lamp igniting apparatus including feedback control

A current flowing through a discharge lamp 4 is detected by a current detecting circuit 5, and the detected current is outputted as a lamp current signal A to a feedback control circuit 7 where a difference between the lamp current signal A and the dimming control signal B is obtained and amplified, and then a amplified signal D is outputted to an adder 12 which adds the amplified signal D to the dimming control signal B to constitute a control signal E. The control signal is fed back to a high frequency power supply 2. When a comparing circuit 15 detects that the light level of the dimming control signal B with respect to the full light becomes higher than or equal to 40% to 60%, the feedback circuit is disconnected by operating a switch 13 provided between an error amplifying circuit 9 and an adder 12 to stop the feedback control. When a light level of a discharge lamp 104 is smaller than or equal to a predetermined value, first and second reference voltage 108a and 108b are switched by a two-stage switching circuit 109. A comparator 107 compares a detection voltage 106 of the discharge lamp 104 with the first reference voltage 108a, or the detection voltage 106 with the second reference voltage 108b. When the voltage of the discharge lamp 104 becomes high, a control circuit 110 supplies to a high frequency power supply 102, a control signal 112 for interrupting, or reducing an output of the high frequency power supply 102.

Discharge lamp igniting apparatus for performing a feedback control of a

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Kanagawa, Japan

Isamu Ogawa