Charge-Couple Device (CCD) Data Capture

Customer Case

The client is involved in developing a charge-couple device (CCD) based system to function as an imaging spectrometer. The spectrometer will image 5×5 mm squares that will form a 50 mm line or 1.5×1.5 mm squares in a 15 mm line. The line is to be imaged on a CCD chip.

In this application the customer needs to simultaneously acquire 10 independent spectra that are 200 pixels long each with 12-bit resolution. The read-out rate is 1000 frames per second for a period of 10 seconds. The 12-bit data is to be stored on the computer to be processed later.

GaGe Case Solution

Let’s analyze the basic data acquisition requirements for this application.

First, the requirement for a single line must be determined as shown below:

200 points x 1000 frames/sec x 10 seconds = 2,000,000 samples

Once the data requirement is determined, the memory needed for this data has to be calculated. Since each sample is 12-bits which is stored in 2 bytes, the memory for this amount of data is 4Mbytes. In order to store ten lines, 40 Mbytes of memory is needed.

Normally images are captured one line at a time in sequence, but, in this case, there are ten lines of data to be captured simultaneously. This means that, instead of a single-channel acquisition system, the system has to be a ten-channel acquisition system.

The solution for this situation is a GaGePC 586 industrial grade computer equipped with five CompuScope 512/ISA boards, with each board having 2 channels and 8M memory.

The 12-bit CompuScope 512 has the resolution needed and, at 5 MSPS, the speed to sample effectively. The 10 seconds of data can be stored in on-board memory prior to downloading to the computer for analysis.

Finally the computer must be equipped with a CompuPower DC-to-DC converter card to ensure that the cards have sufficient power on -12V and -5V power lines.

GaGe Case Recommended Products

  • GaGe PC 586 with CompuPower
  • CompuScope 512 / ISA – 8M Master/Slave System for 5 Cards

Test & Measurement Application Request

We encourage you to contact us and discuss your test & measurement application in more detail with our engineering team. GaGe can provide tailored custom data acquisition hardware and software solutions to meet specific application requirements.