公开(公告)号：US11706392B2

公开(公告)日：2023-07-18

申请号：US17479176

申请日：2021-09-20

Applicant: STMicroelectronics LTD ,  STMicroelectronics S.r.l.

Inventor： Massimo Ratti ,  Eli Yaser ,  Naomi Petrushevsky ,  Yotam Nachmias

IPC: H04N9/31 ,  G06T1/20

CPC classification number: H04N9/3182 ,  G06T1/20 ,  H04N9/3135

Abstract: A light projection system includes a MEMS mirror operating on a mirror drive signal to generate a mirror sense signal resulting from operation of the MEMS mirror based on the mirror drive signal. A mirror driver generates the mirror drive signal from a drive control signal. A controller receives the mirror sense signal from the MEMS mirror, obtains a first sample of the mirror sense signal at a first phase thereof, obtains a second sample of the mirror sense signal at a second phase thereof, wherein the first and second phases are separated by a half period of the mirror drive signal, with the second phase occurring after the first phase, and generates the drive control signal based on a difference between the first and second samples to keep the mirror drive signal separated in phase from the mirror sense signal by a desired amount of phase separation.

公开(公告)号：US11553164B2

公开(公告)日：2023-01-10

申请号：US17012938

申请日：2020-09-04

Applicant: STMicroelectronics Ltd ,  STMicroelectronics S.r.l.

Inventor： Massimo Ratti ,  Eli Yaser ,  Naomi Petrushevsky ,  Yotam Nachmias

IPC: H04N9/31 ,  G06T1/20

Abstract: A light projection system includes a microelectromechanical (MEMS) mirror configured to operate in response to a mirror drive signal and to generate a mirror sense signal as a result of the operation. A mirror driver is configured to generate the mirror drive signal in response to a drive control signal. A zero cross detector is configured to detect zero crosses of the mirror sense signal. A controller is configured to generate the drive control signal as a function of the detected zero crosses of the mirror sense signal.

公开(公告)号：US11474425B2

公开(公告)日：2022-10-18

申请号：US16540557

申请日：2019-08-14

Applicant: STMicroelectronics LTD

Inventor： Eli Yaser ,  Guy Amor ,  Yotam Nachmias ,  Dadi Sharon ,  Sivan Nagola

IPC: G03B21/28 ,  G02B26/08 ,  G02B26/10 ,  G03B21/20

Abstract: A control circuit includes a first control circuit generating a first drive control signal from a pre-drive signal (that is a frequency at which an opening angle of the first and second mirrors is equal) for the first mirror. A second control circuit generates a second drive control signal from the pre-drive signal for the second mirror. First and second drivers generate first and second drive signals for the first and second mirrors from the first and second drive control signals. The first and second drive control signals are generated so that the first and second drive signals each have a same frequency as the pre-drive signal but are different in amplitude from one another to cause the first and second mirrors to move at a same frequency, with a same and substantially constant given opening angle as one another, and in phase with one another.

公开(公告)号：US10805583B2

公开(公告)日：2020-10-13

申请号：US16585751

申请日：2019-09-27

Applicant: STMicroelectronics S.r.l. ,  STMicroelectronics Ltd

Inventor： Massimo Ratti ,  Eli Yaser ,  Naomi Petrushevsky ,  Yotam Nachmias

IPC: H04N9/31 ,  G06T1/20

Abstract: A light projection system includes a GPU that receives video data containing video images, defines a two-dimensional grid (each element of which represents a position of a light beam at a different time), designates which elements of the two-dimensional grid correspond to positions of the light beam in a designated area, designates which elements correspond to positions of the light beam outside of the designated area with some positions outside being designated as calibration positions, maps each element corresponding to positions in the designated area to a corresponding pixel of a frame of a video image, and maps elements corresponding to calibration positions to calibration pixels. An ASIC receives the mapped pixels and mapped calibration pixels from the GPU, and generates a beam position control signal therefrom. A controller controls a movable mirror based on the beam position control signal.