US 12,377,429 B2
Fluidic ejection device with optical blockage detector
Jeffrey M. Raynor, Edinburgh (GB)
Assigned to STMICROELECTRONICS (RESEARCH & DEVELOPMENT) LIMITED, Marlow (GB)
Filed by STMICROELECTRONICS (RESEARCH & DEVELOPMENT) LIMITED
Filed on Mar. 7, 2023, as Appl. No. 18/179,978.
Application 18/179,978 is a division of application No. 16/988,346, filed on Aug. 7, 2020, granted, now 11,623,236.
Prior Publication US 2023/0234086 A1, Jul. 27, 2023
Int. Cl. B41J 2/21 (2006.01); B05B 12/00 (2018.01); B29C 64/209 (2017.01); B29C 64/386 (2017.01); B33Y 50/00 (2015.01); B41J 2/165 (2006.01)
CPC B05B 12/004 (2013.01) [B41J 2/2142 (2013.01); B29C 64/209 (2017.08); B29C 64/386 (2017.08); B33Y 50/00 (2014.12); B41J 2/16579 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method, comprising:
instructing a fluidic ejection device to eject fluid out of a nozzle of the fluidic ejection device, the fluidic ejection device including a light emitting device and a light sensor positioned on opposite sides of the nozzle;
emitting, by the light emitting device, a first light signal towards the nozzle;
measuring, by the light sensor, the first light signal while the fluid ejection device is ejecting fluid out of the nozzle;
instructing the fluidic ejection device to stop ejecting fluid out of the nozzle of the fluidic ejection device;
emitting, by the light emitting device, a second light signal towards the nozzle;
measuring, by the light sensor, the second light signal while the fluidic ejection device has stopped ejecting fluid out of the nozzle; and
determining, by control circuitry, whether the fluidic ejection device is in a normal state, a blocked nozzle state, or an accumulated fluid state based on the measured first light signal and the measured second light signal.