PHIND: an analytic model to predict target acquisition distance with image intensifiers

Area of Science:

• Optics and Photonics
• Image Intensifier Technology
• Vision Science

Background:

• Image intensifiers are crucial for low-light vision.
• Predicting visual range in varying conditions is complex.
• Existing models require further quantification.

Purpose of the Study:

• To elaborate and quantify a calculation scheme for image intensifier visual range prediction.
• To establish a method for calculating recognition distance under diverse conditions.
• To validate the predictive model with experimental data.

Main Methods:

• Utilized physical characteristics of image intensifiers.
• Incorporated observation parameters: target size, contrast, and meteorological visual range.
• Calculated recognition distance based on vertical illuminance.
• Verified predictions using a substantial experimental dataset.

Main Results:

• The elaborated scheme accurately predicts visual range.
• Recognition distance is calculable for any vertical illuminance value.
• Model performance validated across a wide range of targets.
• Target contrast and characteristic size effectively describe recognition distance.

Conclusions:

• The enhanced calculation scheme provides a reliable method for predicting image intensifier performance.
• The model's accuracy is confirmed by experimental validation.
• Practical tools (PHIND FORTRAN, pocket calculator programs) are available.