Arrangement and method for increasing the functional safety of an opto-pyrotechnic initiator
View Patent ↗An arrangement has an opto-pyrotechnic initiator, at least one laser, and an optical fibre, via which the laser radiation of the laser is guided to the opto-pyrotechnic initiator. Also disclosed is a method for improving the safety of such an opto-pyrotechnic initiator. At least one optical filter element having power-dependent or intensity-dependent transmission or reflection is arranged in the beam path of the laser radiation between the laser and the initiating impingement location of the laser radiation in the initiator. The filter element and the beam guidance for the laser radiation are selected such that for a laser power of the laser, that is intended to effect an initiation, the filter element has a higher transmission or reflection or can be switched to a higher transmission or reflection than for a lower laser power by application of an optical or electronic signal that is independent of the laser radiation.
1 . An apparatus comprising:
an opto-pyrotechnic initiator, in which a pyrotechnic mixture can be ignited by laser radiation;
at least one laser which emits the laser radiation; and
an optical fibre, via which the laser radiation is guided to the opto-pyrotechnic initiator,
wherein an optical filter element having power-dependent or intensity-dependent transmission or reflection for the laser radiation is arranged in a beam path of the laser radiation between the laser and an initiating impingement location of the laser radiation in the opto-pyrotechnic initiator,
the filter element is selected, and a beam of the laser radiation is guided in such a way through the filter element that for a laser power of the at least one laser by which an initiation is to be effected in the opto-pyrotechnic initiator in the arrangement, the filter element has a higher transmission or reflection, or can be switched to a higher transmission or reflection by applying an optical signal or an electronic signal that is independent of the laser radiation than at a lower laser power, and
the filter element has a power-dependent or intensity-dependent transmission and includes a saturable absorber.
2 . An apparatus comprising:
an opto-pyrotechnic initiator, in which a pyrotechnic mixture can be ignited by laser radiation;
at least one laser which emits the laser radiation; and
an optical fibre, via which the laser radiation is guided to the opto-pyrotechnic initiator,
wherein an optical filter element having power-dependent or intensity-dependent transmission or reflection for the laser radiation is arranged in a beam path of the laser radiation between the laser and an initiating impingement location of the laser radiation in the opto-pyrotechnic initiator,
the filter element is selected, and a beam of the laser radiation is guided in such a way through the filter element that for a laser power of the at least one laser by which an initiation is to be effected in the opto-pyrotechnic initiator in the arrangement, the filter element has a higher transmission or reflection, or can be switched to a higher transmission or reflection by applying an optical signal or an electronic signal that is independent of the laser radiation than at a lower laser power, wherein the optical signal is laser radiation from at least one further laser, which is coupled into the filter element in such a way that the higher transmission or reflection with the laser power of the at least one laser required to effect the initiation is only attained by superimposing the laser radiation of the at least one laser with the laser radiation of the at least one further laser in the filter element.
3 . The apparatus according to claim 2 , wherein laser beams emitted by the lasers are superimposed at least in the opto-pyrotechnic initiator.
4 . An apparatus comprising:
an opto-pyrotechnic initiator, in which a pyrotechnic mixture can be ignited by laser radiation;
at least one laser which emits the laser radiation; and
an optical fibre, via which the laser radiation is guided to the opto-pyrotechnic initiator,
wherein an optical filter element having power-dependent or intensity-dependent transmission or reflection for the laser radiation is arranged in a beam path of the laser radiation between the laser and an initiating impingement location of the laser radiation in the opto-pyrotechnic initiator,
the filter element is selected, and a beam of the laser radiation is guided in such a way through the filter element that for a laser power of the at least one laser by which an initiation is to be effected in the opto-pyrotechnic initiator in the arrangement, the filter element has a higher transmission or reflection, or can be switched to a higher transmission or reflection by applying an optical signal or an electronic signal that is independent of the laser radiation than at a lower laser power, wherein the optical filter element includes a combination of an optically non-linear medium that has power-dependent or intensity-dependent focusing or defocusing properties, and a following shutter on the beam path of the laser radiation which allows the laser radiation to pass unobstructed only with focusing by means of the non-linear medium.
5 . The apparatus according to claim 4 , wherein the at least one laser includes a plurality of lasers configured to emit the laser radiation, wherein laser beams emitted by the lasers are superimposed at least in the opto-pyrotechnic initiator.
6 . An apparatus comprising:
an opto-pyrotechnic initiator, in which a pyrotechnic mixture can be ignited by laser radiation;
at least one laser which emits the laser radiation; and
an optical fibre, via which the laser radiation is guided to the opto-pyrotechnic initiator,
wherein an optical filter element having power-dependent or intensity-dependent transmission or reflection for the laser radiation is arranged in a beam path of the laser radiation between the laser and an initiating impingement location of the laser radiation in the opto-pyrotechnic initiator,
the filter element is selected, and a beam of the laser radiation is guided in such a way through the filter element that for a laser power of the at least one laser by which an initiation is to be effected in the opto-pyrotechnic initiator in the arrangement, the filter element has a higher transmission or reflection, or can be switched to a higher transmission or reflection by applying an optical signal or an electronic signal that is independent of the laser radiation than at a lower laser power,
wherein the optical filter element includes a thin-film reflector, whose reflectivity changes thermally by a phase transition.
7 . The apparatus according to claim 6 , wherein the optical filter element includes a controllable device for heating the thin-film reflector.
8 . The apparatus according to claim 6 , wherein the at least one laser includes a plurality of lasers configured to emit the laser radiation, wherein laser beams emitted by the lasers are superimposed at least in the opto-pyrotechnic initiator.
9 . The apparatus according to claim 1 , wherein the at least one laser includes a plurality of lasers configured to emit the laser radiation, wherein laser beams emitted by the lasers are superimposed at least in the opto-pyrotechnic initiator.
10 . The apparatus according to claim 1 , wherein the laser radiation is focused onto or into the optical filter element through an optical system.
11 . The apparatus according to claim 1 , wherein the filter element is arranged in the opto-pyrotechnic initiator or between the optical fibre and the opto-pyrotechnic initiator.
12 . The apparatus according to claim 1 , wherein the filter element is arranged inside a housing for the at least one laser or between the at least one laser and the optical fibre.
13 . The apparatus according to claim 1 ,
wherein the filter element is inserted in the optical fibre.
14 . The apparatus according to claim 1 , wherein the laser is a semiconductor laser.