Page 72
Advanced Settings
confocalDT 24x1
6.19
Timing, Measurement Value Flux
The controller operates in cycles for measuring and processing:
1. Exposure: Charging the incoming light in the spectrometer/receiver,
2. Conversion of the video signal as digital values,
3. Computing the distance and thickness, average and so on,
4. Measurement output.
The measured value N is available after three cycles on the output.
The processing of the cycles occurs sequentially in time and parallel in space (pipelin-
ing). After another cycle the next measurement value (N +1) is output.
Each cycle takes about 200 μs at a measuring rate of 5 kHz. The delay between the input
reaction and the output signal is therefore about 600 μs for this measuring rate.
Cycle
1. (N)
2. (N+1)
3. (N+2)
4. (N+3)
Time
200 μs
400 μs
600 μs
800 μs
1. Layer Exposure N Conversion N
Computing N
Output N
2. Layer ---
Exposure N+1
Conversion N+1 Computing N+1
3. Layer ---
---
Exposure N+2
Conversion N+2
4. Layer ---
---
---
Exposure N+3
Fig. 64 Controller timing after switching on
The measured value is available 3 cycles after the incoming trigger signal with active
triggering.
N
N+1
N+2
N+3
N+4
Exposure
Start
analog N
InputTrigIn
Measurement output
digital N
Fig. 65 Timing with triggering, rising edge, one value
N
N+1
N+2
N+3
N+4
Exposure
Input SyncIn
analog N
digital N
analog N+1
digital N+1
analog N-3
digital N-3
analog N-2
digital N-2
analog N-1
digital N-1
Fig. 66 Timing with synchronization, steady state