CAPS Particle Optical Properties
Research grade instrumentation for particle optical extinction & single scattering albedo measurements using our patented Cavity Attenuated Phase Shift (CAPS) technique.
CAPS systems are used worldwide in research laboratories and deployed in field campaigns at fixed sites, in mobile laboratories, and on ship and aircraft platforms.
Aerodyne offers several state-of-the-art optical particle monitors based on the cavity attenuated phase shift (CAPS) technique at fixed wavelengths over the visible spectral range. Similar in nature to cavity ringdown (CRD) detection, the CAPS method relies on producing very long optical paths (several km) using high reflectivity mirrors in a sample cell that is less than 30 cm in length. However, unlike most CRD-based instruments, these monitors utilize a light emitting diode (LED) as an optical source instead of a laser and measure the resultant signal in the frequency domain using a phase shift measurement. As a result, these monitors are highly robust and can be offered at a favorable price compared to CRD-based instruments without loss of performance.
Looking for CAPS Gas Phase Analyzers
CAPS Particle Monitor Models
CAPS PMex Monitor
Accurate and Precise Continuous Monitoring of Particle Optical Extinction (Scattering + Absorption)
- Measurement of ambient optical extinctions at the < 1 Mm-1 level with 1 s response time
- Linear response (0 - 3000 Mm-1)
- No calibration required
-
Automated and autonomous operation:
• Automated background subtraction
• No zero air - Minimal maintenance (periodic change of filter)
- Single or dual wavelengths
- Choice of 6 wavelengths: Ultra Violet (365 nm), Far Blue (405 nm), Blue (450 nm), Green (530 nm), Red (630 nm), Far Red (660 nm)
CAPS PMssa Monitor
Accurate and Precise Continuous Monitoring of Particle Optical Extinction, Scattering, Single Scattering Albedo, and Absorption
- Simultaneous measurement of extinction and scattering on same sample volume
- SSA measurement requires calibration and truncation correction as function of particle size (software provided)
- Scattering and absorption derived from extinction and SSA measurements
- Measurement of optical extinction and scattering at the < 1 Mm-1 level with 1 s response time
- Linear response (1%)
-
Automated and autonomous operation:
o Automated background subtraction
o No zero air - Minimal maintenance (periodic change of filter)
- Choice of 6 wavelengths: Ultra Violet (365 nm), Far Blue (405 nm), Blue (450 nm), Green (530 nm), Red (630 nm), Far Red (660 nm)
| CAPS Measurement Specification | Extinction & Scattering | SSA |
|---|---|---|
|
Range |
0-3,000 Mm-1 |
0-1 |
|
Resolution |
0.01 Mm-1 |
0.01 |
|
Precision (2σ, 1 s) (2σ, 60 s) |
1.5 Mm-1 0.3 Mm-1 |
— 0.03 |
|
Time Response (10-90%) |
1-2 s |
— |
|
Baseline Drift |
Baselines Taken as Often as Required |
|
|
Linearity |
± 10 Mm-1 at 1000 Mm-1 |
— |
|
Flow Rate (lpm) |
0.85 |
— |
|
Dimensions (L x W x H) |
65 cm x 43 cm x 23 cm [19” rack mount, 5U, 24” deep] |
|
|
Weight |
14 Kg |
|
|
Power |
< 40 W |
|