A secondary electron emissive layer resistant to infiltration and fouling. A barrier layer is formed by atomic layer deposition. The barrier layer may be an emissive layer and/or an interlayer. The barrier layer may form an interlayer that is a part of an electron amplifier positioned between an emissive layer and a resistive layer. The barrier layer is resistive to fluorine migration from either the emissive layer or the resistive layer.

A secondary electron emissive layer resistant to infiltration and fouling. A barrier layer is formed by atomic layer deposition. The barrier layer may be an emissive layer and/or an interlayer. The barrier layer may form an interlayer that is a part of an electron amplifier positioned between an emissive layer and a resistive layer. The barrier layer is resistive to fluorine migration from either the emissive layer or the resistive layer.

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.

An electron tube includes a photoelectric surface, an avalanche photodiode, a focusing electrode part that accelerates and focuses the electrons E from the photoelectric surface toward the avalanche photodiode, and a casing including a stem provided with the avalanche photodiode. The stem is provided with a light incident hole through which the light is transmitted, and the periphery of the light incident hole is light-shielded by the stem. The focusing electrode part includes a first region provided with a light passage hole, and a second region provided with an electron passage hole that guides the electrons to the avalanche photodiode. The first region is formed on an axial line that connects the light incident hole and the photoelectric surface. The second region is formed on an axial line that connects the photoelectric surface and the avalanche photodiode.

An electron tube includes a photoelectric surface, an avalanche photodiode, a focusing electrode part that accelerates and focuses the electrons E from the photoelectric surface toward the avalanche photodiode, and a casing including a stem provided with the avalanche photodiode. The stem is provided with a light incident hole through which the light is transmitted, and the periphery of the light incident hole is light-shielded by the stem. The focusing electrode part includes a first region provided with a light passage hole, and a second region provided with an electron passage hole that guides the electrons to the avalanche photodiode. The first region is formed on an axial line that connects the light incident hole and the photoelectric surface. The second region is formed on an axial line that connects the photoelectric surface and the avalanche photodiode.

An electron tube includes a photoelectric surface, an avalanche photodiode, a focusing electrode part that accelerates and focuses the electrons E from the photoelectric surface toward the avalanche photodiode, and a casing including a stem provided with the avalanche photodiode. The stem is provided with a light incident hole through which the light is transmitted, and the periphery of the light incident hole is light-shielded by the stem. The focusing electrode part includes a first region provided with a light passage hole, and a second region provided with an electron passage hole that guides the electrons to the avalanche photodiode. The first region is formed on an axial line that connects the light incident hole and the photoelectric surface. The second region is formed on an axial line that connects the photoelectric surface and the avalanche photodiode.

A sample support includes: a substrate having a plurality of through-holes opening on a first surface and on a second surface; a first member having a plurality of first openings and disposed on the first surface; a second member having a plurality of second openings and disposed on the second surface, and; a bonding member disposed between the first member and the second member; and a conductive layer integrally provided on a region of the second surface corresponding to each of the plurality of second openings. The plurality of through-holes include a plurality of first through-holes located between each of the plurality of first openings and each of the plurality of second openings, and a plurality of second through-holes located between the first member and the second member. Each of the plurality of second openings communicate with each of the plurality of first openings through the plurality of first through-holes.

A secondary electron emissive layer resistant to infiltration and fouling. A barrier layer is formed by atomic layer deposition. The barrier layer may be an emissive layer and/or an interlayer. The barrier layer may form an interlayer that is a part of an electron amplifier positioned between an emissive layer and a resistive layer. The barrier layer is resistive to fluorine migration from either the emissive layer or the resistive layer.

A secondary electron emissive layer resistant to infiltration and fouling. A barrier layer is formed by atomic layer deposition. The barrier layer may be an emissive layer and/or an interlayer. The barrier layer may form an interlayer that is a part of an electron amplifier positioned between an emissive layer and a resistive layer. The barrier layer is resistive to fluorine migration from either the emissive layer or the resistive layer.

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.