US 12,066,383 B2
Optical analyte detection
Hardeep Sanghera, San Jose, CA (US); Ashutosh Shastry, Santa Clara, CA (US); David Piehler, Los Gatos, CA (US); and Yun-Pei Chang, Arcadia, CA (US)
Assigned to Aspida DX Inc., Horsham, PA (US)
Appl. No. 17/312,961
Filed by Aspida DX Inc., Horsham, PA (US)
PCT Filed Dec. 18, 2019, PCT No. PCT/US2019/067290
§ 371(c)(1), (2) Date Jun. 11, 2021,
PCT Pub. No. WO2020/132146, PCT Pub. Date Jun. 25, 2020.
Claims priority of provisional application 62/781,286, filed on Dec. 18, 2018.
Claims priority of provisional application 62/781,300, filed on Dec. 18, 2018.
Claims priority of provisional application 62/781,317, filed on Dec. 18, 2018.
Prior Publication US 2022/0050054 A1, Feb. 17, 2022
Int. Cl. G01N 21/64 (2006.01); B01L 3/00 (2006.01)
CPC G01N 21/648 (2013.01) [B01L 3/508 (2013.01); G01N 21/6428 (2013.01); B01L 2200/025 (2013.01); B01L 2200/04 (2013.01); B01L 2300/0609 (2013.01); B01L 2300/0654 (2013.01); B01L 2300/0663 (2013.01); B01L 2300/0681 (2013.01); G01N 2021/6439 (2013.01); G01N 2021/6482 (2013.01); G01N 2201/0691 (2013.01); G01N 2201/0697 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of reading optical signals from a photonic chip of a removable cartridge held in an optical reader, the method comprising:
modulating a pulsed excitation signal for a laser of the optical reader with a shift signal having a frequency of 1 kHz or greater to form a modulated signal;
adjusting a peak height and duty cycle of the modulated signal to have an average power that is constant;
exciting the laser with the modulated signal to illuminate the photonic chip;
detecting an optical signal from the photonic chip;
generating an output signal from the optical signal; and
demodulating the output signal using the modulated signal to form a demodulated output signal, wherein the demodulated output signal is proportional to a cosine of a phase difference between the modulated signal and the output signal; and
outputting the demodulated output signal.