beijing optics

Hypersonic Flight Effects on Optical Sensors

Hypersonic Flight Effects on Optical Sensors

Hypersonic Flight Effects on Optical Sensors Background: In recent years hypersonic vehicles have received a lot of attention from the media. NASA and various military contractors are spending a lot of time and money investigating the potential for hypersonic flight. Applications include Space Shuttles, high speed aircraft and guided missiles. In order for these vehicles […]

Difficulties associated with UV and IR optics

Difficulties associated with UV and IR optics

Difficulties associated with UV and IR optics Introduction Design and fabrication using UV and IR optics requires consideration of optical materials, surface finish, mechanical and optical fabrication techniques, housing and mounting methods, alignment and test, and cost. These same considerations are addressed when designing and fabricating visible optics, but the magnitude of the problems differ […]

First Order Optics

First Order Optics

First Order Optics 1. INTRODUCTION First order optics are the principles and equations which describe the geometrical imaging of any optical system. The foundations of first order optics are derived from the concept of central projection, collinear transformation and the camera obscura. These foundations will be used to demonstrate the fundamental parameters of an optical […]

Telecentric Lens Tutorial: Precise Imaging.

Tutorial of Telecentric Lens

Tutorial of Telecentric Lens Introduction Nowadays, high accuracy and performance of critical to many machine vision system, a method that use telecentric lens allows highest possible accuracy to be obtained. This tutorial introduced the concept and set up for the object-space telecenric system and image-space telecentric system and advantages of telecentric lens that can impact […]

Tutorial on improving optical system performance.

Tutorial on Strehl ratio, wavefront power series expansion, Zernike polynomials expansion in small aberrated optical systems

Tutorial on Strehl ratio, wavefront power series expansion, Zernike polynomials expansion in small aberrated optical systems 1. Strehl Ratio The wave aberration function, W(x,y), is defined as the distance, in optical path length (product of the refractive index and path length), from the reference sphere to the wavefront in the exit pupil measured along the […]

Tutorial on improving optical system performance.

Tutorial on Strehl ratio

Tutorial on Strehl ratio, wavefront power series expansion, Zernike polynomials expansion in small aberrated optical systems 1. Strehl Ratio The wave aberration function, W(x,y), is defined as the distance, in optical path length (product of the refractive index and path length), from the reference sphere to the wavefront in the exit pupil measured along the […]

Optical windows: key components for optics.

An introduction to optical windows

An introduction to optical windows  ABSTRACT This paper provides and introduction to optical windows. Several aspects of window design are discussed and simple equations to calculate window deformation effects are provided. Several materials that can be used for window substrates are presented and their advantages and disadvantages are discussed. The coating of windows is briefly […]

An introduction to off-axis parabolic mirrors

An introduction to off-axis parabolic mirrors Abstract Off-axis parabolic mirrors (OAPs) can be a useful tool in optical design. OAPs combine the achromatic and diffraction limited imaging properties of a parabolic mirror with the ability to deviate the light path off-axis, which is useful for most imaging systems. However, when used improperly, OAPs can be […]

Mounting optics securely in protective cells.

Potting Optical Elements in Cells

Potting Optical Elements in Cells Introduction Potting optical elements into mechanical cells can ease the manufacturing process for most optical systems. Potting is defined as the process of filling in the space between an optic and its mount with a compliant material that offers resistance to shock, vibration and temperature change. Optical elements are typically […]

Front and side view videoscope lens design.

Front view and panoramic side view videoscope lens system design

Front view and panoramic side view videoscope lens system design 1. Introduction A typical endoscope, either for industrial or medical purpose, is conventionally the front viewing type, which have a limited view angle. There are several designs that can achieve wide field of view, such as fish-eye lens, panoramic reflector, panoramic annular lens (PAL), multi […]

Stray light control, scatter reduction, black coatings.

Stray Light, Scatter, and Black Coatings

Stray Light, Scatter, and Black Coatings Summary This report is a tutorial on basic issues regarding stray light and scatter.  A basic stray light problem is analyzed and a solution of using a black surface is given.  The scatter metric of BRDF is explored and results of a BRDF model are shown.  Other types of […]

A tutorial for designing fundamental imaging systems

A tutorial for designing fundamental imaging systems

A tutorial for designing fundamental imaging systems 1. Abstract This tutorial shows what to do when we design opto-mechanical system for imaging system. Basic principles about designing paraxial systems are introduced. In particular, you can find how to decide specifications, how to select optical elements, how to calculate image shift and how to estimate wavefront […]

Advanced cameras capturing depth and focus.

Plenoptic cameras

Plenoptic cameras What is Plenoptic camera? How it works? What is the application? Plenoptic cameras, known as light field cameras, best capture light fields. How do robotic systems use light field data? What new features does this type of camera create? How do you calibrate them properly? In this article, we take a closer look […]

Focused light propagation in Gaussian beams.

Gaussian Beam Optics

Gaussian Beam Optics I. Introduction In your typical optics lab, most of us, as scientists or engineers, are familiar with  geometrical optics, which assumes that the wavelength of the light approaches zero. When constructing a formalism for light propagation and optical analysis, this assumption allows us to ignore any effects resulting from diffraction and greatly […]