Mastering Relay Lens Design: Enhancing Optical Systems | OFH

Figure 1.  Borescope concept.

Introduction Optical relays, an integral component of various optical systems, play a crucial role when the user’s proximity to the observed object is limited or when specific image transformations are required. A prevalent example of this is found in relay lenses, often employed in scenarios where physical closeness to the object is impractical, as seen […]

Phase Shift Method for distance measurement

Figure 1. (distance measurement)Experimental setup for a Phase-siht range finder. Image from Hungyu He et al.

Optical techniques for distance measurement offer plenty of uses and applications. These techniques are able to measure the distance between two objects without touching them, making them perfect for a variety of situations. Optical techniques are usually the best solution when needing a noncontact method that’s fast or automated. For example, they are often used […]

Screen Scratch Detection System

Screen Scratch Detection System

The resale value of a used smartphone is highly dependent on the quality of the screen. In this project, we demonstrate methods to automatically identify screen scratches and determine screen quality using a custom imaging and illumination layout and computer vision software. Key elements of the design include: The device is a box inside which […]

Cardinal Points

Figure 1. Thick lens optical system. Figure from Newport. Cardinal Points

When I was a young undergrad engineering student, I always found optics to be a very confusing subject. It was not only the equations, but what it looked like hundreds of different definitions involved in even the simplest of optical systems. Some concepts, like radius of curvature, f-number, and focal point were easy to understand […]

Exploring the Scheimpflug Principle: Depth and Clarity in Imaging | OFH

Figure 1. Principal plane for Schiempflug Photography. Image from Fil Hunter, 2006

Introduction The Scheimpflug principle is a fundamental concept in optics, particularly in the realm of photography and imaging. Named after its inventor Theodor Scheimpflug, this principle provides a systematic approach to achieving extended depth of field in photographs and precise focus control in optical systems. At its core, the Scheimpflug principle addresses the challenge of […]

Understanding Rayleigh Range: Key to Laser Beam Propagation

Figure 1. Gaussian beam traveling in free-space. The beam waist (w0) is the smallest diameter of the beam. Zr is the Rayleigh Range, b is the confocal distance, and ? is the divergence.

Introduction When working with lasers it is important to understand the physical parameters that define system performance. While some of these specifications may be readily recognizable, such as wavelength and divergence, others may be lesser-known, yet equally critical metrics. For instance, concepts like the M-factor, beam caustic, and Rayleigh Range often have immense significance in […]