Product Manual

34 Specifications Welch Allyn Spot Vision Screener
Weight (lbs.): ~2.55
Wireless Network: 802.11 b/g/n
Operating Temperatures (°C): +10 to +40
Operating Humidity: 30% to 95% Relative Humidity (non-condensing)
Storage/Shipping Temperatures (°C): 0 to +50
Storage/Shipping Humidity: 0% to 95% Relative Humidity (non-condensing)
Storage/Shipping Atmospheric Pressure: 800 hPA to 1060 hPA
Expected Battery Life: 2.5 Years (Under Normal Usage)
Measurements
Note Screening results provide an output that is either in- or out-of-range, accompanied
by the appropriate statement in the device output display (“Screening Complete or
“Complete Eye Exam Recommended). The displayed message is intended to prompt the
caregiver to assess whether the subject should be referred to an eye care specialist for
further evaluation or simply be monitored at future screenings.
Refraction
Spherical Equivalent:
• Range: -7.50D to +7.50D in 0.25D increments
• Accuracy: -3.50D to 3.50D, ± 0.50D
-7.50D to < -3.50D, ± 1.00D
> 3.50D to 6.00D, ± 1.00D
Cylindrical:
• Range: 0.00D to +3.00D in 0.25D increments
• Accuracy: 0.00D to 1.50D, ± 0.50D
> 1.50D to 3.00D, ± 1.00D
Cylindrical Axis:
• Range: 1 to 180 degrees in 1-degree increments
• Accuracy: ± 5 degrees (for cylinder values > 0.5D)
Pupil size:
• Range: 4.0 mm to 9.0 mm in 0.1 mm increments
• Accuracy: ± 0.1mm
Pupil distance:
• Range: 35mm to 80 mm in 1 mm increments
• Accuracy: ± 1 mm
Time per measurement:1 s
• Measuring distance: 1 m ± 5 cm
• Fixation target:Random visual pattern and audible sound
Measurement principle: Optical reflex