Application-dependent considerations when selecting cameras with CMOS-, CCD and InGaAssensors in the wavelength range 300 to 1700nm

Transcription

1 Application-dependent considerations when selecting cameras with CMOS-, CCD and InGaAssensors in the wavelength range 300 to 1700nm Alastair Slater, Sales Manager Northern Europe, May 2015

2 Allied Vision Technologies Profile Foundation: 1989, Headquarters: Stadtroda (Thüringen), Employees: aprox. 265 (2015) Know how: Development and production of high-quality digital cameras for industrial and scientific imaging Research & Development Hardware- and software development of digital cameras for the visible and the infrared spectrum Standard cameras and also camera solutions for OEM customers Production Company-owned production sites (cleanroom) in Stadtroda and Osnabrück (Germany); Burnaby (Canada) Service Consulting teams for distribution and support, worldwide, 24/5 Quality standards Compliance with ISO-9001 and ISO 13485

3 Optical sensors & electromagnetical spectrum Visible range Parts of the electromagnetic spectrum

4 Image Information Depending on Spectral Ranges

5 Silicon quantum detectors: CCD & CMOS CCD (analog sensor) CMOS (active pixel sensor) A/D conversion outside the sensor A/D conversion on the sensor

6 Sensors for the visible spectrum: CCD- and CMOS sensors Advantages of CCD: High image quality: Low spatial noise (FPN) Typically low dark current High fill factor (relation of the photo sensitive area to the whole pixel area) generally by larger pixels Perfect global shutter Increased sensitivity Good signal quality at low light Modern CCDs with multi tap technologies n times readout speed compared to single tap sensors Advantages of CMOS: High frame rates, even at high resolution Faster and more flexible readout (e.g. several AOIs) High dynamic range HDR mode Acquisition of contrast-rich and extremely bright objects No blooming or smear contrary to CCD Integrated control circuit on the sensor chip More cost-effective and less power consumption than comparable CCD sensors

7 Sensors for the visible spectrum: CCD- and CMOS sensors Advantages of CCD: High image quality: Advantages of CMOS: High frame rates, even at high resolution Low spatial noise Recent (FPN) CMOS sensors deliver: Faster and more flexible readout Typically low dark current (e.g. several AOIs) improved global shutter High fill factor (relation low dark of the and photo spatial sensitive noise as well High dynamic range area to the whole Good pixel image area) generally quality in by low light HDR condition mode Acquisition of contrast-rich and larger pixels higher quantum efficiency too extremely bright objects Perfect global shutter No blooming or smear contrary to CCD Together with the existing advantages in speed and cost Increased sensitivity which makes CMOS sensors suitable Integrated for a lot control of vision circuit applications! the sensor chip Good signal quality at low light More cost-effective and less power Modern CCDs with multi tap technologies consumption than comparable CCD sensors n times readout speed compared to single tap sensors

8 CCD artifacts blooming and smear Blooming: Charge overflow (> full well capacity) between neighboring pixels Corrective action: reduction of the incoming light Smear: During readout photons generate a charge in the vertical shift register Corrective action : increase of the exposure time, use of a mechanical or LCD shutter, use of flash illumination

9 Sony sensors ExView HAD CCD II TM ICX 687 (2,8 MP), ICX 674 (2,8 MP), ICX 692 (0,95 MP), ICX694 (6 MP), ICX814 (9MP) Improved CCD structure Super HAD CCD II Increased sensitivity (+ 6 db) Improved on-chip color filter Increased sensitivity for shorter wave lengths (blue), More homogenous characteristics of the spectral sensitivity

10 Applications for CCD cameras Acquisition with minimal noise Low light intensities Microscopy Fluorescence microscopy High resolution microscopy Astronomy High resolution and high quality images Bioluminescence / Chemoluminescence Science Full Frame CCD Imagers, e.g. KAF-6303E Bigeye G-629B Cool

11 CMOSIS CMV2000 & CMV4000 NIR sensors ( up to 1000 nm) CMOS variants with increased NIR sensitivity Sensor with 12 µm epitaxial silicon layer increased absorption of photons in the red and NIR spectrum Increase of the quantum efficiency (QE) for wave lengths > 600 nm Doubling of the 900 nm from 8 % to 16 %

12 High dynamic range mode (CMOS) Dedicated exposure control: The pixels saturation level is controlled by knee points The response curve between the knee points is linearly controlled The exposure time is automatically controlled For applications with high light intensities (e.g. laser welding, high-contrast objects, night shots with spot lights) Sensor Output High Illumination Low Illumination V2 V1 V0 texpo0 texposure texpo1 texpo2

13 Sony Exmor and Exmor R CMOS Sensors Pregius global shutter pixel technology Front-illuminated pixel technology Exmor STARVIS Visibility under starlight Back-illuminated pixel technology Exmor R Source: html

14 Sony Exmor CMOS sensors e.g. IMX 174 (1/1.2, 2,35 MP, 5,86 µm pixel size) IMX Sony s 1 st global shutter CMOS High sensitivity: >75% nm High DNR (> 70 db) based on Sony s CCD pixel technology, saturation capacity: ~ e- fully shielded memory - low dark current noise and nearly no unwanted parasitic light High frame rate column parallel A/D conversion (IMX174: 164 fps@10 bit, 128 fps@12 bit) Analog CDS + digital CDS = dual noise reduction Noiseless high-speed data transfer via LVDS higher possible shutter speed, less image blur of fast moving objects and high frame rates MV and ITS applications

15 Python - global shutter CMOS Sensors New global shutter CMOS sensor family with resolutions of 0.3 MP (VGA) to 5 MP with 4.8 µm x 4.8 µm Pixel size Suitable for general purpose industrial imaging applications in machine vision as well as for security and surveillance applications including intelligent transportation systems (ITS) Features: in-pixel CDS (ipcds) technology enabling global shutter imaging with single digit noise High frame rates 620 frames per VGA (1/4 ) 420 frames per SVGA (1/3.6 ) 175 frames per SXGA (1/2 ) High NIR sensitivity High dynamic range Multiple Region Of Interest PYTHON 0.3/0.5/1.3 MP

16 Applications for CMOS cameras (high speed) Fast tracking - motion analysis with frames per second Applications: Motion analysis for sports and wildlife Golf swing analysis with camera Mako G-030 Generation of slow motion pictures

17 Usage of CMOS and CCD predicted reversal within 2 years Users Manufacturers Source:

18 Infrared light spectrum

19 What is Short-wave Infrared? Visible nm CCD/CMOS NIR Enhanced CCD/CMOS NIR nm Standard InGaAs Extended InGaAs SWIR nm ,000 1,700 Wavelength [nm] 2,200 2,500

20 InGaAs sensor - seeing the invisible Spectral sensitivity ( nm) Indium bumps on each pixel of InGaAs array and readout IC

21 What differs a SWIR camera from a classic Machine Vision camera? 1 InGaAs Detector Sensitivity between 900 and 1,700 nm High complexity level in the production process Defect pixels on every sensor Non-uniform pixel behavior Higher dark current than CCD, CMOS 3 Advanced image correction features Non-uniformity correction (NUC) Defect Pixel Correction Background Correction 2 Cooling Capability Due to the higher Dark Current of InGaAs sensors, cooling is necessary

22 Applications for SWIR cameras Checking the contacts of a TFT or underlying structures in a wafer (> 1100 nm: Silicon appears transparent) Electroluminescence inspection of solar cells (Silicon emits 1150 nm) Inspection of hypodermic needles inside sleeve (> 1100 nm: some plastics appear transparent)

23 Applications for SWIR cameras Hot-End Glass Inspection Monitoring of glass temperature uniformities and cooling rate from 250 C to 800 C Interior and exterior walls inspection Improvement of yield and quality Reference temps: White hot steel ~1200 C Melting point of aluminum 660 C Water boils at 100 C Uncooled camera at 38 C Human body at 37 C, radiates at ~ 10 μm Water freezes at 0 C

24 Applications for SWIR cameras Hyperspectral Imaging (HIS) combines digital imaging with spectroscopy to obtain detailed information across multiple ranges of the electromagnetic spectrum Applications: Recycling & Plastic Sorting Geology & Mineral Inspection Pharmaceutical Quality Control Food & Agriculture Medical e.g. Disease Diagnosis

25 Applications for SWIR cameras Print industry: Banknotes inspection (> 1200 nm: some printing characteristics become invisible, while the layer underneath becomes visible) Verifying the authenticity of art works (SWIR penetrates the deeper layers of the applied paint)

26 Outlook Goldeye G-033 SWIR TEC1 High-speed SWIR Camera Resolution: 640 x 512; 15 µm pixel size Fastest SWIR camera with GigE Vision interface Benchmark values: Resolution 8-Bit Mode 12-Bit Mode 14-Bit Mode Full Resolution ~ 290 fps ~ 230 fps ~ 170 fps 640 x 480 ~ 300 fps ~ 250 fps ~ 190 fps 320 x 240 ~ 900 fps ~ 900 fps ~ 700 fps

27 The Right Camera for Each Application

28 Thank You/Q&A Allied Vision Technologies GmbH Taschenweg 2a Stadtroda Germany