Wide field of view optical module for linear sensor

• US 10,511,794 B2
• Filed: 10/12/2017
• Issued: 12/17/2019
• Est. Priority Date: 01/17/2017
• Status: Active Grant

• Current Assignee: Six Degrees Space Ltd
• Original Assignee: Six Degrees Space Ltd
• Inventors: Lieberman, Klonymus Sholom, Greenspan, Daniel
• Primary Examiner(s): Lee, John R
• Application Number:
  US15/782,504
• Publication Number:
  US 20180205899A1
• Time in Patent Office: 796 Days
• CPC Class Codes: G02B 27/0081 with means for altering, e.g. enlarging, the entrance or exit pupil
• CPC Class Codes: G02B 3/02 with non-spherical faces G02B3/10 takes precedence
• CPC Class Codes: G02B 3/04 with continuous faces that are rotationally symmetrical but deviate from a true sphere , e.g. so called "aspheric" lenses
• CPC Class Codes: G02B 3/06 with cylindrical or toric faces
• CPC Class Codes: G06T 7/246 using feature-based methods, e.g. the tracking of corners or segments
• CPC Class Codes: H01L 27/14625 Optical elements or arrangements associated with the device
• CPC Class Codes: H04N 25/701 Line sensors

Abstract

A sensing module includes a high speed, linear image sensor and an optical unit facing the sensor. The unit includes an optical element having a curved surface and a covering on an outward surface of the optical element. The covering has a slit formed therein. The optical unit images a wide field of view onto a single pixel of the linear sensor, wherein light impinging normal to the slit, at any location along the slit, is imaged on a central pixel of the linear sensor while light impinging at a non-normal angle to the slit, at any location along the slit, is imaged on a non-central pixel of the linear sensor.

Claims

1. A sensing module comprising:

a linear image sensor; and

an optical unit comprising;

an optical element having a curved surface; and

a covering on a flat outward surface of said optical element, said covering having a slit formed therein,

said optical unit facing said sensor with said slit perpendicular to a longitudinal axis of said linear sensor and to image a wide field of view onto a single pixel of said linear sensor, wherein light impinging normal to said slit, at any location along said slit, is imaged on a single central pixel of said linear sensor while light impinging at one of a plurality of non-normal angles to said slit at any location along said slit, is imaged on an associated one of a plurality of non-central pixels of said linear sensor,

wherein said optical element is a freeform lens comprising;

an aspheric optical surface with variable optical power located on an inward surface of said lens facing said sensor, wherein said surface focuses light incident on said slit at each vertical elevation angle across a linear sensor and wherein the optical power of said lens varies to maintain a constant magnification.

2. The sensing module of claim 1 and wherein said optical element is a single monolithic lens.

3. The sensing module of claim 2 and wherein a magnification of said optical element is varied to map a plurality of vertical lines to each one of said pixels of said linear sensor with minimal distortion.