Patent ID: 11915921
Assignee: DENKA COMPANY LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 3:
4. A method for manufacturing an electron source comprising steps of:
(a) preparing a plurality of first members each provided with a columnar portion made of a first material having an electron emission characteristic;
(b) preparing a plurality of second members each of which has a higher work function than the first material, and in each of which a hole extending in a direction from one end face toward the other end face is formed;
(c) selecting one first member from the plurality of first members and selecting one second member from the plurality of second members; and
(d) pressing the columnar portion of the selected first member into the hole of the selected second member,
wherein each of the columnar portions of the plurality of first members has a substantially triangular cross-sectional shape,
each of the holes of the plurality of second members has a substantially circular cross-sectional shape,
in step (c), a set of the first member and the second member is selected from the plurality of first members and the plurality of second members under the following conditions, and
in step (d), by pressing the columnar portion into the hole of the second member, a portion of a side surface of the columnar portion abuts an inner surface of the hole of the second member, thereby fixing the columnar portion to the second member,
wherein the conditions are such that a diameter R2 of a circumscribed circle of the substantial triangle is set larger than a diameter R1 of the hole, and when the substantial triangle is disposed in a prepared circle having the same diameter as the diameter R1 of the hole, at least two corners of the substantial triangle protrude into the prepared circle.