US 9,812,283 B2
Charged particle source
Shuai Li, Fremont, CA (US)
Assigned to HERMES MICROVISION, INC., Hsinchu (TW)
Filed by Hermes Microvision Inc., Hsinchu (TW)
Filed on Jan. 12, 2017, as Appl. No. 15/404,440.
Application 15/404,440 is a division of application No. 14/964,221, filed on Dec. 9, 2015.
Claims priority of provisional application 62/089,609, filed on Dec. 9, 2014.
Prior Publication US 2017/0125202 A1, May 4, 2017
Int. Cl. H01J 37/143 (2006.01); H01J 37/28 (2006.01); H01J 3/20 (2006.01); H01J 37/09 (2006.01)
CPC H01J 37/143 (2013.01) [H01J 3/20 (2013.01); H01J 37/09 (2013.01); H01J 37/28 (2013.01); H01J 2237/0453 (2013.01); H01J 2237/063 (2013.01); H01J 2237/141 (2013.01); H01J 2237/1415 (2013.01); H01J 2237/2806 (2013.01); H01J 2237/2817 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An electron source, comprising:
an emitter, providing an electron beam along an optical axis;
an upper magnetic field generator, generating a first magnetic field;
a lower magnetic field generator, generating a second magnetic field; and
an anode, extracting the electron beam from the emitter,
wherein the first magnetic field superposed with the second magnetic field provides a magnetic field strength, wherein said magnetic field strength is zero at a tip of the emitter and increases along the optical axis to a local maximum immediately away from the tip between the tip and the anode.