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Measuring the Behavioral Effects of Intraocular Scatter
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Seeker head geometric parameters influence on the hypersonic aero-optical effect
Applied Optics
|September 14, 2023
Summary
Hypersonic vehicles distort imaging systems due to aero-optical effects. This study quantifies these effects, finding that larger cone angles worsen imaging quality, while increasing line-of-sight angle reduces image deviation.
Area of Science:
- Aerospace Engineering
- Optical Physics
- Fluid Dynamics
Background:
- Hypersonic flight vehicles generate significant aero-optical effects impacting imaging system performance.
- Distortions arise from density variations in the flow field around the vehicle.
Purpose of the Study:
- To quantitatively analyze the aero-optical effects on a 2D optical seeker model.
- To investigate the influence of seeker head radius, cone angle, and ray incidence on image distortion.
- To determine optimal parameters for minimizing imaging aberrations.
Main Methods:
- Numerical simulation to obtain flow field density data.
- Ray tracing method to compute aero-optical effects.
- Evaluation using parameters like image deviation, boresight error, and Strehl ratio.
Main Results:
- Image deviation decreases as the line-of-sight (LOS) angle increases.
- For a 40mm seeker radius and cone angles >20°, image deviation stabilizes.
- Boresight error (BSE) decreases with increasing LOS angle (small cone angle) and cone angle, stabilizing above 40°.
- Strehl ratio decreases with increasing cone angle, indicating poorer imaging quality.
Conclusions:
- Larger optical seeker cone angles degrade imaging quality.
- Increasing the line-of-sight angle can mitigate image deviation.
- Flow field density variations have a more significant impact than shock wave proximity on optical path difference.
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