用于快速自发光源的高速变形光瞳共轭狭缝光谱仪
A high-speed anamorphic pupil-conjugate slit spectrograph for rapid, self-luminous sources
- Vision Research（视觉研究）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
该研究提出一种高速变形光瞳共轭狭缝光谱仪，通过光学设计消除光谱图像漂移，结合高速CMOS相机，经表征后用于10 kHz下的硝化纤维素燃烧光谱分析，成功识别多种化学物种。
中文摘要 AI 辅助
我们提出了一种狭缝成像光谱仪，其波长配准特性取决于仪器本身，而非前置光学系统的指向或光源位置。内部远心4f中继系统将系统光阑置于仪器内部，柱面透镜则将狭缝孔径置于横向位置仅编码光源角度的平面（ABCD矩阵公式中的A=0共轭）。因此，光源的横向运动或前置光学系统的指向不会导致传感器上的光谱图像漂移，从而消除了事件中不存在的化学物种的非物理配准，以及动态重新校准的需求。此外，高速CMOS相机的使用消除了时间平均光谱线和混叠噪声。我们对波长校准进行了表征：使用氦放电灯，二次拟合的RMS残差为0.12 nm，用氖放电灯验证，采用相同校准的RMS残差为0.13 nm；光谱分辨率：R≈639，在最佳狭缝宽度设置下FWHM为0.92 nm，在仪器轮廓下限处R≈783，FWHM为0.75 nm；指向不变性：氦587.6 nm线漂移的RMS为0.29 nm，峰峰值为1.03 nm，与孔径光阑位于前置光学光瞳的相同仪器相比，漂移减少了近100倍。我们以10 kHz、99 μs的曝光时间对点燃的硝化纤维素进行了燃烧光谱分析，使用从氦放电灯转移的不变波长校准，识别出钠、钾、钙、CaOH和铷化学物种。
英文摘要
We present a slit imaging spectrograph whose wavelength registration is a property of the instrument rather than of the pointing of the fore-optic or the position of the source. An internal telecentric 4f relay places the system stop within the instrument while a cylindrical lens places the slit aperture at a plane where transverse position encodes source angle only (an $A = 0$ conjugate in the ABCD matrix formulation). As a result, the lateral motion of the source or the pointing of the fore-optic does not cause the spectral image illuminating the sensor to wander, thus eliminating any non-physical registration of chemical species not present in the event and the need for on-the-fly recalibration. Additionally, the use of a high-speed CMOS camera eliminates temporally averaged spectral lines and aliasing noise. We characterize wavelength calibration (He discharge lamp, quadratic fit, RMS residual 0.12 nm, verified with Ne discharge lamp, same calibration, RMS residual 0.13 nm), spectral resolution (R $\approx$ 639, FWHM 0.92 nm at the optimal slit width setting, R $\approx$ 783, FWHM 0.75 nm at the instrument profile floor), and pointing invariance (He 587.6 nm line wander 0.29 nm RMS, 1.03 nm peak-to-peak, a nearly 100x reduction relative to the same instrument with the aperture stop at the fore-optic pupil). We perform combustion spectroscopy on ignited nitrocellulose at 10 kHz, 99 $μ$s exposure time, identifying Na, K, Ca, CaOH, and Rb chemical species using the unchanged wavelength calibration transferred from the helium discharge lamp.
