Apparatus and method for projecting a variable pattern of electromagnetic energy

Abstract

According to an embodiment, an interrogator includes a beam generator operable to scan a variable-power beam across a field of view, a detector aligned to receive an electromagnetic signal from the field of view and generate a corresponding detection signal, and a controller operatively coupled to the detector and the beam generator and operable to vary the power of the beam as it scans across the field of view responsive to the detection signal. According to an embodiment, an illumination system includes an illumination source operable to provide spatially-varying illumination, a detector configured to receive scattered energy from the spatially-varying illumination, and an electronic controller operable to vary the spatial variation of the illumination responsive to the scattered energy received by the detector. According to an embodiment, a method includes illuminating a field of view with a variable power illumination pattern, receiving scattered light from the field of view, and modifying the pattern of the variable power illumination responsive to the scattered light

Description

FIELD OF THE INVENTION [0001] The present invention relates to scanned beam systems and variable illumination systems, and more particularly to control systems for scanned beam imagers and variable illuminators. BACKGROUND OF THE INVENTION [0002] The field of imaging can be divided into one-dimensional (1D) or linear imaging, two-dimensional (2D) imaging, and three-dimensional imaging. [0003] Examples of 1D imagers include bar code devices using linear pixelated detectors, including for instance charge-coupled-device (CCD) and complementary-metal-oxide-silicon (CMOS) detectors. Linear pixelated imagers typically include illumination to reduce exposure time and ambient lighting requirements, often in the form of a sheet of light formed by a light emitting diode (LED) or LED array. Line-Scan cameras are a specific type of 1D pixelated imager. In line-scan cameras, a second dimension, usually perpendicular to the detector array, is provided by movement of the object or phenomenon being...

AI Technical Summary

Benefits of technology

The present invention relates to imaging systems that automatically adjust the intensity of illumination based on the characteristics of the scene being captured. This can be done by using a variable-intensity source that casts light across the entire field-of-view, or by using an illuminator that is responsive to the darkness of different regions in the scene. The invention also includes methods for differentially illuminating the field-of-view and for using a scanned beam system to capture images with enhanced dynamic range. Additionally, the invention relates to laser scanners that can improve performance by modulating the intensity of the laser beam based on image attributes, detector sensitivity, and the synchronization of the illuminator and detection system. The invention also includes methods for probing the field-of-view to gather image data and for controlling the illuminator to improve the overall performance of the imaging system.

Problems solved by technology

In such situations, peak power consumption and illuminator cost vs.

Unfortunately, flash photography suffers from dynamic range issues, having a tendency to overexpose nearby objects while underexposing distant parts of the FOV.

Often, the resulting images have too much contrast, foreground objects being over-exposed and the background underexposed.

These attempts to manually manipulate the illumination intensity across the field of view are frequently laborious and require a high degree of artistry.

Images