ultrasonic op• Data kinds: table → table
• Call: import fullseye as fs; fs.ledger.sam_frequency_tradeoff(stack, void_diameter, water_path=0.001, f_number=3.0, interface=None, k_res=1.02, f_min=1000000.0, f_max=5000000000.0, n_grid=600, bandwidth=0.6, n_sigma_gate=5.0) (to call the implementation directly, import ultrasound; ultrasound.sam_frequency_tradeoff(stack, void_diameter, water_path=0.001, f_number=3.0, interface=None, k_res=1.02, f_min=1000000.0, f_max=5000000000.0, n_grid=600, bandwidth=0.6, n_sigma_gate=5.0); from the registry, opsacoustics.get("sam_frequency_tradeoff"))
Optimal SAM frequency for a void of given size at a buried interface: lateral fill (1 - 2^-(a/w)^2, w = k_res*lambda_w*F#) against two-way attenuation; closed form when all losses go as f^2 (table).
> The detailed description below is the original text — the summary and the headings are translated.
信号 S(f) = η(f) · exp(−L(f))、η = 1 − 2^{−(a/w)²} はボイド(直径 a)の中心にガウスの往復 PSF(半値全幅 w = k/f、k = k_res c_w F#)が当たったときの充填率、L(f) = 2 α_w(f) z_w + 2 Σ_{j<interface} α_j(f) d_j(水の経路と上の層の往復減衰 [Np])。減衰がすべて f²(L = β f²)なら dlnS/df = 0 から f* = (k/a) · sqrt(log2(1 + a² ln2 / (β k²)))(小さなボイドの極限で 1/√β)。それ以外は対数格子で探して有界の 1-D 最適化で詰める。
返り: freqs fwhm fill loss_np loss_db signal f_opt(数値) f_opt_closed(閉形式が立つときだけ、そうでなければ None)beta k fwhm_at_opt f_number_min(臨界角の上限)。
時間の分解能の下限も返す: 表面エコーと界面のエコーの間隔 t_sep(積層の往復時間)がパルスの包絡線の n_sigma_gate σ_t(ゲートの半幅 2σ_t + 裾 3σ_t)より短いと、表面エコーの裾がゲートに入る。σ_t = FWHM_PER_SIGMA / (2π · bandwidth · f) なので f_min_time = n_sigma_gate · 2.3548 / (2π · bandwidth · t_sep)、f_opt_usable = max(f_opt, f_min_time)(表面の界面(interface=0)なら下限 0)。★ボイドの反射 |R| は周波数によらず 1 とみなす(薄い空気の層では ~1)。Raises ValueError: 印の無い積層、直径 ≤ 0、f_min ≥ f_max、F# が臨界角の上限より小さい、減衰が 0 (最適周波数が存在しない — 上へ行くほど良い)。
• acoustic_condition_monitoring family guide
• Sample-data catalog (download URLs / licences) — 2-D uses skimage.data (BSD/public domain) plus synthetic images; 3-D lists download URLs for real data sources (Stanford, PDS, …).
• Operator provenance and references — the sources of the research/methods this op family came from.
• The canonical algorithm (author, year) and its uses are named in the family usage guide above.
• poc_sam_hybrid_bonding_voids — py -3.11 examples/poc_sam_hybrid_bonding_voids.py
table as input)istft · acoustic_interface_coefficients · pulse_echo_ascan · sam_cscan · echo_phase_polarity
ultrasonic)acoustic_material_table · acoustic_layer_stack · acoustic_interface_coefficients · pulse_echo_ascan · sam_cscan · echo_phase_polarity
*Provenance: ultrasound.py — ACOUSTICS operator registry. This per-op note is generated by tools/opdocs.py md (do not hand-edit).*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.