基于前向光线追迹技术的单光场相机空间分辨率研究

田杏; 曹丽霞

doi:10.37188/CO.2025-0119

基于前向光线追迹技术的单光场相机空间分辨率研究

doi: 10.37188/CO.2025-0119

cstr: 32171.14.CO.2025-0119

田杏,
曹丽霞^,

中国计量大学计量测试与仪器学院, 杭州 310018

基金项目: 国家自然科学基金（No. 12302370）

详细信息

作者简介:
田　杏，女，硕士研究生，主要从事光场成像系统优化和应用方面的研究。E-mail：1933270289@qq.com

曹丽霞（1989—），女，浙江磐安人，博士，讲师，研究生导师，2022年于东南大学获得博士学位。现为中国计量大学计量测试与仪器学院讲师。主要从事光场成像、层析成像和流体可视化方面的研究。E-mail：caolx2019@gmail.com

中图分类号: O438.1
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出版历程
- 收稿日期: 2025-09-17
- 录用日期: 2025-11-25
- 网络出版日期: 2025-12-03

Research on spatial resolution of a single light field camera based on forward ray tracing technique

TIAN Xing,
CAO Li-xia^,

College of Metrology Measurement and Instrument, China Jiliang University, Hangzhou 310018, China

Funds: Supported by National Natural Science Foundtion of China (No. 12302370)

More Information

Corresponding author: caolx2019@gmail.com

摘要

摘要:
目的：由于光场相机将空间与角度信息联合采样，光场相机的空间分辨率随三维位置的变化而改变，因此表现出三维性、复杂性以及显著的非均匀特性。在三维场景的重建过程中，光场相机的空间分辨率会影响可恢复的空间细节和深度分辨率，从而影响三维重建的准确性。因此，对光场相机的空间分辨率进行计算与分析，对于高分辨率和低分辨率区域的识别十分重要。方法：本文利用前向光线追迹技术的高精度的优点，研究了一种基于前向光线追迹技术的光场相机空间分辨率计算方法。对不同微透镜阵列排列方式下的光场相机1.0和2.0的空间分辨率进行了定量计算和比较。进一步研究了不同的主镜头逆放大率（M_l）对光场相机深度分辨率的影响。结果：结果表明，光场相机在物平面与光轴交点附近以外的区域具有较高的深度分辨率。结论：光场相机2.0在(0,0,0)附近区域的深度分辨率优于光场相机1.0。对于正方形排列的微透镜阵列，光场相机2.0的横向分辨率较光场相机1.0略有提升。光场相机1.0的深度分辨率随着M_l的增大而逐渐降低。
- 光场相机 /
- 空间分辨率 /
- 重建 /
- 光线追迹 /
- 深度分辨率
Abstract:
Objetive: Since the light field camera (LFC) simultaneously samples spatial and angular information, its spatial resolution varies with the three-dimensional (3D) position, thereby exhibiting three-dimensionality, complexity, and pronounced non-uniformity. In the process of 3D scene reconstruction, the spatial resolution of the LFC affects the recoverable spatial details as well as the depth resolution, thereby influencing the accuracy of the 3D reconstruction. Therefore, calculating and analyzing the spatial resolution of the LFC is crucial for identifying the high and low resolution regions. Method: In this paper, a calculation method for the spatial resolution of an LFC is explored based on the forward ray-tracing technique, which has the advantage of high accuracy. The spatial resolutions of LFC 1.0 and LFC 2.0 under different microlens array configurations are quantitatively calculated and compared. In addition, the effects of the inverse magnification (M_l) of the main lens on the depth resolution of the LFC are investigated. Result: The results show that the LFC exhibits higher depth resolution in regions away from the intersection of the object plane and the optical axis. Conclusion: The depth resolution of LFC 2.0 near the region of (0,0,0) is better than that of LFC 1.0. For a microlens array arranged in a square pattern, the lateral resolution of LFC 2.0 shows a slight improvement over that of LFC 1.0. The depth resolution of the LFC 1.0 gradually decreases as M_l increases.
- light field camera /
- spatial resolution /
- reconstruction /
- ray tracing /
- depth resolution

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图 1 光场相机的成像原理示意图

Figure 1. Schematic diagram of the imaging principle of the light field camera

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图 2 微透镜阵列排列方式示意图

Figure 2. Schematic diagram of the arrangement of the MLA

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图 3 点光源的位置示意图

Figure 3. Positions schematic of the point light source

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图 4 沿Z轴的深度分辨率

Figure 4. Depth resolution along Z axis

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图 5 沿X轴的横向分辨率

Figure 5. Lateral resolution along X axis

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图 6 沿Y轴的横向分辨率

Figure 6. Lateral resolution along Y axis

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图 7 前向光线追迹和逆向光线追迹技术的的空间分辨率计算结果对比

Figure 7. Comparison of spatial resolution calculation results between forward ray tracing and backward ray tracing techniques

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图 8 沿Z轴的深度分辨率

Figure 8. Depth resolution along Z axis

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图 9 沿X轴的横向分辨率

Figure 9. Lateral resolution along X axis

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图 10 沿Y轴的横向分辨率

Figure 10. Lateral resolution along Y axis

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图 11 沿Z轴的深度分辨率

Figure 11. Depth resolution along Z axis

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图 12 沿X轴的横向分辨率

Figure 12. Lateral resolution along X axis

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图 13 沿Y轴的横向分辨率

Figure 13. Lateral resolution along Y axis

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图 14 沿Z轴的深度分辨率

Figure 14. Depth resolution along Z axis

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图 15 沿X轴的横向分辨率

Figure 15. Lateral resolution along X axis

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图 16 沿Y轴的横向分辨率

Figure 16. Lateral resolution along Y axis

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图 17 不同M_l在(0,0,Z)的深度分辨率

Figure 17. Depth resolution of different M_l at (0,0,Z)

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表 1 光场相机1.0的光学参数

Table 1. Parameters of the light field camera 1.0

d₁ (mm)	d₂ (mm)	f_m (mm)	f (mm)	l₁ (mm)	l_m (mm)	P_m (mm)	P_x (μm)
0.6	-	0.6	100	200	200	0.1045	5.5

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表 2 光场相机2.0的光学参数

Table 2. Parameters of the light field camera 2.0

d₁ (mm)	d₂ (mm)	f_m (mm)	f (mm)	l₁ (mm)	l₂ (mm)	P_m (mm)	P_x (μm)
0.54	5.4	0.6	100	200	200	0.1045	5.5

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表 3 不同M_l下光场相机1.0的光学参数

Table 3. Parameters of the light field camera 1.0 with different M_l

d₁ (mm)	f_m (mm)	f (mm)	M_l	l₁ (mm)	l_m (mm)	P_m (mm)	P_x (μm)
0.6	0.6	100	1	200	200	0.1045	5.5
0.6	0.6	100	1.5	250	166.667	0.1045	5.5
0.6	0.6	100	2	300	150	0.1045	5.5
0.6	0.6	100	2.5	350	140	0.1045	5.5

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