Pensia Lavlesh, Kumar Manoj, Kumar Raj
CSIR-Central Scientific Instruments Organisation, Sector 30C, Chandigarh 160030, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
Sensors (Basel). 2024 Jan 23;24(3):731. doi: 10.3390/s24030731.
Digital holography (DH) is an important method for three-dimensional (3D) imaging since it allows for the recording and reconstruction of an object's amplitude and phase information. However, the field of view (FOV) of a DH system is typically restricted by the finite size of the pixel pitch of the digital image sensor. We proposed a new configuration of the DH system based on Fresnel's bi-mirror to achieve doubling the camera FOV of the existing off-axis DH system which leveraged single-shot acquisition and a common-path optical framework. The dual FOV was obtained by spatial frequency multiplexing corresponding to two different information-carrying beams from an object. Experimental evidence of the proposed dual FOV-DH system's viability was provided by imaging two different areas of the test object and an application to surface profilometry by measuring the step height of the resolution chart which showed excellent agreement with an optical profiler. Due to the simple configuration, the proposed system could find a wide range of applications, including in microscopy and optical metrology.
数字全息术（DH）是三维（3D）成像的一种重要方法，因为它能够记录和重建物体的幅度和相位信息。然而，DH系统的视场（FOV）通常受到数字图像传感器像素间距有限尺寸的限制。我们提出了一种基于菲涅耳双镜的DH系统新配置，以实现将现有离轴DH系统的相机视场翻倍，该系统利用单次采集和共光路光学框架。通过对来自物体的两条不同信息承载光束进行空间频率复用，获得了双视场。通过对测试物体的两个不同区域进行成像，提供了所提出的双视场DH系统可行性的实验证据，并通过测量分辨率测试图的台阶高度将其应用于表面轮廓测量，结果与光学轮廓仪显示出极佳的一致性。由于配置简单，所提出的系统可找到广泛的应用，包括在显微镜和光学计量学中的应用。
