An ultraviolet flame detector (100) includes a housing (102) having an opening (103) at a first end (101a) of the housing (102), and a window structure (104) arranged to cover the opening (103) of the housing (102). A photocathode (106) is arranged to a second end (101b) of the housing (102) so that the photocathode (106) is facing inside the housing (102). An anode wire (108) is arranged between the window structure (104) and the photocathode (106). The anode wire (108) is configured to travel transversally across the housing (102). The ultraviolet flame detector (102) is filled with a gas.

An ultraviolet flame detector (100) includes a housing (102) having an opening (103) at a first end (101a) of the housing (102), and a window structure (104) arranged to cover the opening (103) of the housing (102). A photocathode (106) is arranged to a second end (101b) of the housing (102) so that the photocathode (106) is facing inside the housing (102). An anode wire (108) is arranged between the window structure (104) and the photocathode (106). The anode wire (108) is configured to travel transversally across the housing (102). The ultraviolet flame detector (102) is filled with a gas.

The electron tube includes a vacuum container having a light transmitting substrate, a photocathode provided on an inner surface of the light transmitting substrate, an anode provided in the vacuum container, and a prism. The prism includes a bottom surface bonded to an outer surface of the light transmitting substrate, a light incident surface, and a light reflecting surface configured to further reflect light, which is incident to the photocathode through the prism and the light transmitting substrate and reflected at an interface between the photocathode and the vacuum space, so that the light is re-enter the photocathode. The light reflecting surface has an outwardly convex curved surface shape. The light incident surface is located inward of an imaginary spherical surface that is along the light reflecting surface.

A photoelectric tube includes a housing including a light transmitting portion, an electron emitting portion including a photoelectric surface disposed inside the housing, an electron capturing portion disposed between the light transmitting portion and the photoelectric surface inside the housing, and a conductive layer disposed on a light transmitting portion side of at least a part of the electron capturing portion to face the photoelectric surface inside the housing and configured to allow light to pass therethrough.

A photoelectric tube includes a housing including a light transmitting portion, an electron emitting portion including a photoelectric surface disposed inside the housing, an electron capturing portion disposed between the light transmitting portion and the photoelectric surface inside the housing, and a conductive layer disposed on a light transmitting portion side of at least a part of the electron capturing portion to face the photoelectric surface inside the housing and configured to allow light to pass therethrough.

A photoelectric tube includes a housing including a light transmitting portion, an electron emitting portion held by a recess provided in the housing, the electron emitting portion including a concave photoelectric surface facing a light transmitting portion side inside the housing, and an electron capturing portion disposed between the light transmitting portion and the photoelectric surface inside the housing. At least a part of the electron capturing portion is located inside a region on an inside of the photoelectric surface.

A night vision system along with an image intensifier tube and method for shuttering the continued draw of electrons from an electron multiplier are provided. The night vision system includes the electron multiplier, or possibly two electron multipliers, each comprising a silicon membrane. A shutter voltage is applied between a first surface and a substantially parallel, opposed second surface of the silicon membrane to discontinue draw of electrons through the electron multiplier and for substantially discontinuing display of an image from the image intensifier tube under certain bright light conditions. Utilizing a global shutter control on the electron multiplier, and the significantly lower voltage for such control mitigates power consumption within the image intensifier, as well as electromagnetic interference and delay response time. A relatively low voltage negative bias shutter voltage on only the electron multiplier selectively provides global shutter to the image intensifier device.

A night vision system along with an image intensifier tube and method for shuttering the continued draw of electrons from an electron multiplier are provided. The night vision system includes the electron multiplier, or possibly two electron multipliers, each comprising a silicon membrane. A shutter voltage is applied between a first surface and a substantially parallel, opposed second surface of the silicon membrane to discontinue draw of electrons through the electron multiplier and for substantially discontinuing display of an image from the image intensifier tube under certain bright light conditions. Utilizing a global shutter control on the electron multiplier, and the significantly lower voltage for such control mitigates power consumption within the image intensifier, as well as electromagnetic interference and delay response time. A relatively low voltage negative bias shutter voltage on only the electron multiplier selectively provides global shutter to the image intensifier device.

The invention discloses a photocathode comprising an amorphous substrate such as a glass substrate (110) presenting an input face that will receive incident photons and a back face opposite the front face. Nanowires (120) made from at least one III-V semiconducting material are deposited on the back face of the substrate and extend from this face in a direction away from the front face. The invention also relates to a method for manufacturing such a photocathode by MBE.

A solar generator can include a photon-enhanced thermionic emission generator with a cathode to receive solar radiation. The photon-enhanced thermionic emission generator can include an anode that in conjunction with the cathode generates a first current and waste heat from the solar radiation. A thermoelectric generator can be thermally coupled to the anode and can convert the waste heat from the anode into a second current. A circuit can connect to the photon-enhanced thermionic emission generator and to the thermoelectric generator and can combine the first and the second currents into an output current.