scholarly journals Tri-Dimensional Optical Inspection Based on Flexible Image Guide: First Step Toward 3D Industrial Endoscopy

2012 ◽  
Author(s):  
Erwan Dupont ◽  
Frédéric Lamarque ◽  
Christine Prelle ◽  
Tanneguy Redarce
Keyword(s):  
Optical Design ◽  
Digital Camera ◽  
Reconstruction Algorithm ◽  
Depth Of Field ◽  
Image Guide ◽  
Optical Inspection ◽  
Circular Field ◽  
Dimensional Shape ◽  
Mechanical Objects ◽  
532 Nm

3D optical endoscopy is now a major challenge to allow the high resolution inspection of industrial equipments. The proposed instrument is based on a flexible image guide (70 000 fibres) and a Digital Micro mirror Device (DMD, 1024 × 768 “on-off” micro mirrors). The optical design is as follows: the light emitted by a 532 nm laser diode is dynamically structured by the DMD chip as a fringes pattern which is phase-shifted due to the active control of the DMD chip and projected onto an object on a circular field of 6 mm in diameter. Due to a telecentric and binocular arrangement that creates a stereoscopic angle, it is possible to get a depth of field of 2 mm along the optical axis without keystone distortions and few disturbances created by defocus and coma aberrations. Then, images are captured by a 1024 × 768 digital camera (not yet moved away by fibres) at 15 fps and directly used in the reconstruction algorithm to access the tri-dimensional shape of the unpainted object. The results are compared to incoherent white light results obtained with white painted mechanical objects. The lateral resolution is 31.3 μm and the RMS axial resolution is 10 μm for the laser-based design after speckle attenuation.

scholarly journals Optical Inspection Systems for Axisymmetric Parts with Spatial 2D Resolution

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1218
Author(s):  
Aleksandr Kulchitskiy
Keyword(s):  
Control System ◽  
Optical System ◽  
Measurement Accuracy ◽  
Experimental Studies ◽  
Digital Camera ◽  
Digital Cameras ◽  
Bodies Of Revolution ◽  
Optical Inspection ◽  
Inspection Systems ◽  
Projection Error

The article proposes a solution to the problem of increasing the accuracy of determining the main shaping dimensions of axisymmetric parts through a control system that implements the optical method of spatial resolution. The influence of the projection error of a passive optical system for controlling the geometric parameters of bodies of revolution from the image of its sections, obtained by a digital camera with non-telecentric optics, on the measurement accuracy is shown. Analytical dependencies are derived that describe the features of the transmission of measuring information of a system with non-telecentric optics in order to estimate the projection error. On the basis of the obtained dependences, a method for compensating the projection error of the systems for controlling the geometry of the main shaping surfaces of bodies of revolution has been developed, which makes it possible to increase the accuracy of determining dimensions when using digital cameras with a resolution of 5 megapixels or more, equipped with short-focus lenses. The possibility of implementing the proposed technique is confirmed by the results of experimental studies.

Optical Design of Endoscopic Telecentric Measuring Apparatus

2013 ◽  
Vol 552 ◽  
pp. 325-328
Author(s):  
Qiong Wu ◽  
Yang Xiang ◽  
Bin Yang ◽  
Qian Song ◽  
Li Jie Hou ◽  
...  
Keyword(s):  
Surface Defects ◽  
Optical Design ◽  
Mirror Image ◽  
Depth Of Field ◽  
Modulation Transfer ◽  
Master Cylinder ◽  
Precision Measuring ◽  
Pentagonal Prism ◽  
Airy Disk ◽  
To Receive

Endoscopic telecentric apparatus is a precision measuring instrument which consists of optical, mechanical and electrical technologies. It can be applied in real-time accurate test to detect the position, shape and wall surface defects of brake master cylinder. This paper designed an optical system with Zemax, it can be used in endoscopic telecentric apparatus. The system has 4mm linear field of view, the line of vision is 90°,the magnification is 0.75×,the depth of field is 6mm.The value of modulation transfer function (MTF) is close to the diffraction limit, the resolution of the system is up to 3 and the spot diagrams of all configurations are smaller than Airy disk, the total track is less than 300mm. It adopts 1/6CCD to receive image, the measurement accuracy reaches to 0.03mm.The system uses pentagonal prism to realize 90°line of vision, it is convenient to assemble and avoids the mirror image. The image quality is good and the design meets the requirement.

scholarly journals Designing a video laryngoscope imaging system with a 7mm blade for neonatal patients

2018 ◽  
Vol 201 ◽  
pp. 04002
Author(s):  
Ming-Ying Hsu ◽  
Wen-Tse Hsiao ◽  
Han-Chao Chang
Keyword(s):  
Imaging System ◽  
Optical Design ◽  
Intrathoracic Pressure ◽  
Video Laryngoscope ◽  
Depth Of Field ◽  
Birth Canal ◽  
Core Technology ◽  
Ventilation Failure ◽  
Optical Imaging System ◽  
Small Mouth

When a newborn infant has been pushed from the birth canal due to ventilation failure while using a resuscitation mask, the doctor must implement infant intubation and other emergency steps to keep the baby alive. However, due to the excessively small mouth area of a newborn or premature infant, the doctors are unable to view the glottis entrance, which can lead to either a failed intubation or longer intubation time, thereby resulting in either a drop in oxygen levels or a rise in intrathoracic pressure. Although the normal video laryngoscope with a 12mm metal blade certainly improves this type of difficult intubation, nevertheless, doctors often complain that the depth of field (DOF) is insufficient and the width of the blade is too wide when performing intubation on neonatal patients. Therefore, this study aims to develop two modules of infant’s video laryngoscope, an ultra-thin 7mm metal blade and an optical imaging system, the core technology of which includes an optical design of a 2.5mm lens and verifications of imaging quality. In order to allow physicians to determine the infant’s airway position immediately and to avoid the binocular disparity from a physician while giving intubation, this study has simulated the optical properties of monolithic lenses while designing the imaging system, allowing the doctor to have a clearer and undistorted image within the field of view.

scholarly journals Macro Imaging with Digital Cameras

2003 ◽  
Vol 11 (4) ◽  
pp. 32-35 ◽  
Author(s):  
Bryan Burnett ◽  
Steven Blaauw
Keyword(s):  
Digital Camera ◽  
Depth Of Field ◽  
Zoom Lens ◽  
Attractive Alternative ◽  
Digital Cameras ◽  
Lens System ◽  
Charged Couple Device

Advances in charged couple device (CCD) design, low cast processor power, cheap memory and dropping prices of digital cameras over the last few years have made the CCD digital camera art attractive alternative to the film camera for many imaging applications. This is especially true in macro imaging where it appears likely that digital cameras will replace film cameras (curiously, Long (2001), says otherwise). As will be described here, a digital camera equipped with a quality macro-zoom lens, generates images with a depth of field (e.g., Fig. 1) that greatly surpass images produced by a film camera with a comparable lens system.

scholarly journals An inexpensive system for imaging the contents of multi-well plates

2018 ◽  
Vol 74 (12) ◽  
pp. 797-802 ◽  
Author(s):  
Andrew Bohm
Keyword(s):  
Imaging System ◽  
Three Dimensional ◽  
Digital Camera ◽  
Numerical Control ◽  
Depth Of Field ◽  
Still Images ◽  
Python Script ◽  
Translation Stage ◽  
G Code ◽  
Wood Carving

An inexpensive system for automated imaging of the contents of 12-, 24- and 96-well plates has been built. The xyz stage is constructed from parts from a light-duty computer numerical control wood-carving/engraving machine, and the Arduino-based board was wired so that it can trigger still images or movies though a microscope-mounted digital camera. The translation stage provides reproducible three-dimensional movement of the sample over a volume of 160 mm in x, 100 mm in y and 40 mm in z. A Python script generates the G-code command file that scans the plate and collects a series of z-stacked images of each sample. A second Python script automates the calculation of images with a digitally enhanced depth of field. The imaging system is currently being used to facilitate screening for protein crystals, but it could be used to automate the imaging of many other types of samples in multi-well plates.

Application of ISO Standard Methods to Optical Design for Image Capture

2020 ◽  
Vol 2020 (9) ◽  
pp. 240-1-240-7
Author(s):  
Peter D. Burns ◽  
Don Williams ◽  
John Griffith ◽  
Heidi Hall ◽  
Scott Cahall
Keyword(s):  
Modulation Transfer Function ◽  
Optical Design ◽  
Digital Camera ◽  
Optical Systems ◽  
Modulation Transfer ◽  
Optical Aberrations ◽  
Image Capture ◽  
Camera System ◽  
Iso Standard ◽  
Standard Methods

The ISO 12233 standard for digital camera resolution includes two methods for the evaluation of camera performance in terms of a Spatial Frequency Response (SFR). In many cases, the measured SFR can be taken as a measurement of the camera-system Modulation Transfer Function (MTF), used in optical design. In this paper, we investigate how the ISO 12233 method for slantededge analysis can be applied to such an optical design. Recent improvements to the ISO method aid in the computing of both sagittal and tangential MTF, as commonly specified for optical systems. From computed optical simulations of actual designs, we apply the slanted-edge analysis over the image field. The simulations include the influence of optical aberrations, and these can present challenges to the ISO methods. We find, however, that when the slanted-edge methods are applied with care, consistent results can be obtained.

Optical design for large depth of field

2016 ◽  
Author(s):  
Yang Shen ◽  
Hu Wang ◽  
Pan Yue ◽  
Yaoke Xue ◽  
Jie Liu ◽  
...  
Keyword(s):  
Optical Design ◽  
Depth Of Field ◽  
Large Depth
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