JAI CV-A33CL Functions and Operations, Basic functions, Cmos Sensor, Pixel principle

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To column processing
Buffer amplifier
2 x 10 bit digital shift register
Fig. 7. CMOS principle layout
Video process
Photo diode
Start exposure
1
Light
Fig. 8. Pixel principle.
Charge capacitor
4
Pixel memory
Reset memory
Stop exposure 2
Read row 3

CV-A33CL

6. Functions and Operations

In the following the format shown in “7.3. CV-A33CL command list” are used for function commands and parameters.

6.1. Basic functions

The CV-A33CL camera is a progressive scan camera with 10 or 8 bit video output in single channel Camera Link.

Programmable partial scan, where the start line and the number of lines can be selected with 1 line increment is also available.

There are 4 modes: Normal continuous, and 3 trigger modes: Edge Pre-Select (EPS), Pulse Width Control (PWC) and Auto Trigger.

The accumulation is LVAL a-synchronous.

In the following some of the functions are shown in details.

6.1.1. CMOS Sensor

The CMOS sensor principle layout is shown. The sensor is an array of active photosensitive pixels. The global shutter is working simultaneously on all pixels. The readout can be random row by row. 4 columns are feed through a 4 to 1 multiplexer to an A/D converter. The digitized row signals are placed in a vertical register by a 1 to 4 multiplexing. From here it is read out with the pixel clock pulses, even if the window of interest has fewer columns. The frame speed depends only of the height of the window, not of the width.

Pixel principle and column processing with A/D converting is shown below.

 

R

T

O

W

I

 

M

D

I

E

N

C

O

G

D

 

Control

E

and

 

set up

 

Pixel

Column

Process

and A/D

6.1.2. Pixel principle

Each pixel consists of a sensing part, a pixel memory and an amplifier. The function can in short be

described. The photo diode and charge capacitor is reset when switch 1 is closed. The signal accumulation starts when sw 1 open. The charge is transferred to the

pixel memory capacitor when sw 2 close. The accumulation stop when sw 2 open, and the signal is now temporary stored in the memory capacitor. After

reset of the charge capacitor, a new accumulation can start. The signal on the pixel memory capacitor is read out to the column by the read row signal. The memory can now be reset.

With this construction all pixels will integrate at the same time, (Global shutter). The resulting image is temporary stored in the pixel memory during read out, while a new exposure can be started.

All timing is set up in the timing block by an internal serial link.

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Contents CV-A33CL CV-A33CL Standard Composition Main FeaturesGeneral Locations and Functions LocationsPin Assignment Pin Multi-connector DC-IN/TriggerDigital Output Connector for Camera Link Input and Output Circuits EEN outputCamera Link interface CV-A33 Camera Camera Link CableFunctions and Operations Basic functionsCmos Sensor Pixel principleCV-A33 Cmos Sensor array Cmos Sensor principle diagramColumn Process Window of Interest Auto Trigger Window of InterestSensor layout and timing Effective image formatVertical timing Normal mode. Full frame Horizontal timing Normal mode. Full frameLval a-synchronous accumulation Lval a-synchronous accumulationTiming for window of interest Window of interestInput/Output of Timing Signals Input of Timing SignalsOutput of Timing Signals Trigger ModesEdge Pre-select Mode Continuous Operation Non triggeredVertical timing for edge pre-select min. exposure Pulse Width Control Mode Vertical timing for pulse width control min. exposureAuto trigger Mode Vertical timing for auto trigger functionOther Functions Configuring the CameraSwitch setting inside RS-232C control CV-A33CL command list Parameter RemarksCamera Control Tool for CV-A33 Window from camera control toolSpectral sensitivity External Appearance and DimensionsSpecifications Specification table CV-A33CLAppendix PrecautionsTypical Sensor Characteristics Camera type Users Mode Settings Users ModificationsUsers Record