Overview
We developed three radiometric LW320-12 lenses, enabling microscopic temperature measurement of features down to 3µm. Lenses are manufactured from Germanium, Zinc Selenide, and Zinc Sulfide with anti-reflective coatings for maximum transmission in the long wave infrared region. Each lens is designed for maximum sensitivity, long working distance, and with minimum distortion for clear, precise imaging. The threaded interface reduces the space required to attach the lens while maximizing thermal uniformity between the lens and camera body to maintain the high measurement accuracy.
Applications
Microscopic temperature analysis of electronics of:
- Electronics
- Optical devices
- MEMS devices
- Biological samples
- Chemical reactions
- Materials
Features
Comprehensive Calibration
Each lens is calibrated while installed on the camera, resulting in unsurpassed accuracy and measurement uniformity across the entire field-of-view.
Specifications
Optics
Lens | IS320 10 Micron Lens PN0931 | IS320 5 Micron Lens PN0930 | IS320 3 Micron Lens PN0929 |
Pixel Resolution | 10 µm | 5 µm | 3 µm |
Focus | Fixed | Fixed | Fixed |
Sensitivity | <50mk | <100mk | <200mk |
Working Distance | 10 mm | 4.9 mm | 4.2 mm |
Field of View | 3.2 x 2.4 mm | 1.6 x 1.2 mm | 0.96 x 0.72 mm |
Focal Length | 40.3 mm | 8.3 mm | 10.5 mm |
Numerical aperture | 0.6 | 0.7 | 0.75 |
Working F/# | 1.09 | 1.41 | 2.62 |
Object Space NA | 0.39 | 0.60 | 0.65 |
Depth of Field | ±40µm | ±25µm | ±15µm |
Measurement
Calibration Range † | Low range: 0 to 80°C * High range: 0 to 300°C | Low range: 0 to 100°C * High range: 0 to 300°C | Low Range 0 to 140°C * High range: 0 to 300°C |
Sensitivity (NETD) ‡ | Low range: < 40 mK (60 Hz) High range: < 80 mK (60 Hz) | Low range: < 60 mK (60 Hz) High range: < 100 mK (60 Hz) | < 100 mK < 200 mK |
Accuracy | Low range: ± 2°C High range: ± 2°C or 2% of reading § | Low range: ± 3°C High range: ± 3°C or 3% of reading § | Low range: ± 4°C High range: ± 4°C or 4% of reading § |
* Micros low range calibrations are optimized for highest sensitivity and may have reduced calibration range.
† The calibration range stated in the specification indicates the range of black-body temperatures used during calibration. Temperature measurements outside of the stated range may be able to be performed but may not meet the specified measurement accuracy.
‡ Noise Equivalent Temperature Difference (NETD) specifies the smallest temperature difference that can be detected. The value stated is NETD at 60 Hz frame rate. Activating real-time image averaging can improve NETD but will increase the measurement response time.
§ whichever is greater
Optical Magnification Comparison
Optical magnification is calculated by dividing the sensor pixel size (12µm) by the lens image pixel size.
| Image pixel size | Optical Magnification |
| 10µm | 12/10 = 1.2x |
| 5µm | 12/5 = 2.4x |
| 3µm | 12/3 = 4x |
Width of a line in micrometers in USAF Resolving Power Test Target 1951
| Group Number | -2 | -1 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | |
| Element | |||||||||||||
| 1 | 2000.00 | 1000.00 | 500.00 | 250.00 | 125.00 | 62.50 | 31.25 | 15.63 | 7.81 | 3.91 | 1.95 | 0.98 | |
| 2 | 1781.80 | 890.90 | 445.45 | 222.72 | 111.36 | 55.68 | 27.84 | 13.92 | 6.96 | 3.48 | 1.74 | 0.87 | |
| 3 | 1587.40 | 793.70 | 396.85 | 198.43 | 99.21 | 49.61 | 24.80 | 12.40 | 6.20 | 3.10 | 1.55 | 0.78 | |
| 4 | 1414.21 | 707.11 | 353.55 | 176.78 | 88.39 | 44.19 | 22.10 | 11.05 | 5.52 | 2.76 | 1.38 | 0.69 | |
| 5 | 1259.92 | 629.96 | 314.98 | 157.49 | 78.75 | 39.37 | 19.69 | 9.84 | 4.92 | 2.46 | 1.23 | 0.62 | |
| 6 | 1122.46 | 561.23 | 280.62 | 140.31 | 70.15 | 35.08 | 17.54 | 8.77 | 4.38 | 2.19 | 1.10 | 0.55 |
Figure 1: USAF 1951 chart from 10µm lens perspective
Figure 2: USAF 1951 chart from 5µm lens perspective
Figure 3: USAF 1951 chart from 3µm lens perspective