1. An operating device of an electronic apparatus comprising:
a rotatable operating knob protruding from a panel; and
stopper means for preventing rotational operation of the operating knob,
wherein, when the power of the electronic apparatus is turned off, the rotational operation of the operating knob is prevented by a stopper part of the stopper means,
when the power of the electronic apparatus is turned on, the rotational operation of the operating knob can be performed by releasing the stopper part of the stopper means, and
the power of the electronic apparatus is at least turned off by operation of an engine key of a vehicle.
2. The operating device of an electronic apparatus according to claim 1, wherein the power of the electronic apparatus is turned on by the operation of the engine key of the vehicle, such that the rotational operation of the operating knob can be performed.
3. The operating device of an electronic apparatus according to claim 1, the device further comprising:
a switch unit which is manually operable for turning on or off the power of the electronic apparatus,
wherein, when the power of the electronic apparatus is turned on by an operation of the switch unit, the operating knob can rotate by releasing the stopper part of the stopper means, and
when the power of the electronic apparatus is turned off by the operation of the switch unit, the rotational operation of the operating knob is prevented by the stopper part of the stopper means.
4. The operating device of an electronic apparatus according to claim 3,
wherein, when the power of the electronic apparatus can be turned on by the operation of the engine key or by the operation of the switch unit, turning onoff of the power of the electronic apparatus can be performed by the switch unit, and
when the power of the electronic apparatus is turned off from ON state by the operation of the engine key, the rotational operation of the operating knob is prevented by the stopper part of the stopper means.
5. The operating device of an electronic apparatus according to claim 1, wherein the stopper means has a solenoid.
6. The operating device of an electronic apparatus according to claim 1,
wherein the operating device has a plurality of the operating knobs and a plurality of the stopper means; and
the stopper means are arranged correspondingly to the respective operating knobs.
7. The operating device of an electronic apparatus according to claim 5, wherein the operating knob is attached to a rotatable member of a rotary electrical component, and the stopper means are arranged correspondingly to the operating knob or the rotatable member.
8. An operating device of an electronic apparatus comprising:
a rotatable operating knob protruding from a panel; and
a stopper having a stopper part operative to prevent rotational operation of the operating knob when the power of the electronic apparatus is turned off and operative to permit rotational operation of the operating knob when the power of the electronic apparatus is turned on by release of the stopper part,
wherein an engine key of a vehicle is operative to at least turn off the power of the electronic apparatus.
9. The operating device of an electronic apparatus according to claim 8, wherein the engine key is operative to turn on the power of the electronic apparatus such that the rotational operation of the operating knob is performable.
10. The operating device of an electronic apparatus according to claim 8, further comprising a manually operable switch unit which is operable to turn on or off the power of the electronic apparatus such that when the power of the electronic apparatus is turned on by an operation of the switch unit, the operating knob is rotatable by releasing the stopper part of the stopper, and when the power of the electronic apparatus is turned off by the operation of the switch unit, the rotational operation of the operating knob is prevented by the stopper part of the stopper.
11. The operating device of an electronic apparatus according to claim 8, wherein the stopper further comprises a solenoid.
12. The operating device of an electronic apparatus according to claim 8,
wherein the operating device has a plurality of the operating knobs and a plurality of the stoppers; and
the stoppers are arranged correspondingly to the respective operating knobs.
13. The operating device of an electronic apparatus according to claim 12, wherein the operating knobs are each attached to a rotatable member of a rotary electrical component, and each stopper is arranged correspondingly to the operating knob or the rotatable member.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An external modulator monitoring device for monitoring an external modulator, comprising:
a mixing unit to mix optical signals modulated by the external modulator and optical signals not modulated by the external modulator, so as to obtain a multiple branches of mixed optical signals;
an electrical differential unit to convert the multiple branches of mixed optical signals into corresponding multiple branches of electrical signals, and perform a differential processing on voltages of the multiple branches of electrical signals to obtain differential signals; and
a power detection unit to detect power of the differential signals;
wherein
the mixing unit is a 3\xd73 optical coupler to mix optical signals modulated by the external modulator and optical signals not modulated by the external modulator into three branches of mixed optical signals;
the electrical differential unit is a differential filter unit comprising:
three photovoltaic transformers respectively to convert the three branches of mixed optical signals into electrical signals, so as to obtain three branches of electrical signals;
three filters respectively to filter the three branches of electrical signals, so as to obtain three branches of filtered electrical signals;
three differential units to obtain differences between the voltages of every two branches of filtered electrical signals among the three branches of filtered electrical signals, so as to obtain three branches of differential signals,
the power detection unit comprising:
three squarers respectively to square the three branches of differential signals, so as to obtain three branches of square values; and
an adder to obtain a sum of the three branches of square values.
2. An external modulator monitoring device for monitoring an external modulator, comprising:
a mixing unit to mix optical signals modulated by the external modulator and optical signals not modulated by the external modulator, so as to obtain a multiple branches of mixed optical signals;
an electrical differential unit to convert the multiple branches of mixed optical signals into corresponding multiple branches of electrical signals, and perform a differential processing on voltages of the multiple branches of electrical signals to obtain differential signals; and
a power detection unit to detect power of the differential signals;
wherein
the mixing unit is a 3\xd73 optical coupler to mix optical signals modulated by the external modulator and optical signals not modulated by the external modulator into three branches of mixed optical signals;
the electrical differential unit is a differential filter unit comprising:
three photovoltaic transformers respectively to convert the three branches of mixed optical signals into electrical signals, so as to obtain three branches of electrical signals;
three differential units to obtain differences between the voltages of every two branches of electrical signals among the three branches of electrical signals, so as to obtain three branches of differential signals,
three filters respectively to filter the three branches of differential signals, so as to obtain three branches of filtered differential signals;
the power detection unit comprising:
three squarers respectively to square the three branches of filtered differential signals, so as to obtain three branches of square values; and
an adder to obtain a sum of the three branches of square values.
3. The external modulator monitoring device according to claim 1 or claim 2, wherein the mixing unit is a symmetrical mixing unit.
4. The external modulator monitoring device according to claim 1 or claim 2, wherein the external modulator is a single MZ modulator or a multi-branch MZ modulator.
5. An external modulator monitoring method for monitoring an external modulator, comprising:
mixing optical signals modulated by the external modulator and optical signals not modulated by the external modulator, so as to obtain a multiple branches of mixed optical signals;
converting the multiple branches of mixed optical signals into corresponding multiple branches of electrical signals;
performing a differential processing on voltages of the multiple branches of electrical signals to obtain differential signals; and
detecting power of the differential signals;
wherein
the mixing mixes optical signals modulated by the external modulator and optical signals not modulated by the external modulator into three branches of mixed optical signals;
the performing comprising:
respectively converting the three branches of mixed optical signals into electrical signals, so as to obtain three branches of electrical signals;
respectively filtering the three branches of electrical signals, so as to obtain three branches of filtered electrical signals;
obtaining differences between the voltages of every two branches of filtered electrical signals among the three branches of filtered electrical signals, so as to obtain three branches of differential signals,
the detecting comprising:
respectively squaring the three branches of differential signals, so as to obtain three branches of square values; and
obtaining a sum of the three branches of square values.