Low-cost laser detection system with a 360-deg horizontal field of view

AbstractMicroscopy enables fast and effective diagnostics. However, in resource-limited regions microscopy is not accessible to everyone. Smartphone-based low-cost microscopes could be a powerful tool for diagnostic and educational purposes. In this paper, the imaging quality of a smartphone-based microscope with four different optical parameters is presented and a systematic overview of the resulting diagnostic applications is given. With the chosen configuration, aiming for a reasonable trade-off, an average resolution of 1.23 μm and a field of view of 1.12 mm2 was achieved. This enables a wide range of diagnostic applications such as the diagnosis of Malaria and other parasitic diseases.

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Face recognition in an intelligent door lock with ResNet model based on deep learning

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189624 ◽

2021 ◽

pp. 1-11

Author(s):

Suphawimon Phawinee ◽

Jing-Fang Cai ◽

Zhe-Yu Guo ◽

Hao-Ze Zheng ◽

Guan-Chen Chen

Keyword(s):

Face Recognition ◽

Detection System ◽

Low Cost ◽

Ease Of Use ◽

Raspberry Pi ◽

Training Methods ◽

Graphics Recognition ◽

Face Images ◽

The Face ◽

Door Lock

Internet of Things is considerably increasing the levels of convenience at homes. The smart door lock is an entry product for smart homes. This work used Raspberry Pi, because of its low cost, as the main control board to apply face recognition technology to a door lock. The installation of the control sensing module with the GPIO expansion function of Raspberry Pi also improved the antitheft mechanism of the door lock. For ease of use, a mobile application (hereafter, app) was developed for users to upload their face images for processing. The app sends the images to Firebase and then the program downloads the images and captures the face as a training set. The face detection system was designed on the basis of machine learning and equipped with a Haar built-in OpenCV graphics recognition program. The system used four training methods: convolutional neural network, VGG-16, VGG-19, and ResNet50. After the training process, the program could recognize the user’s face to open the door lock. A prototype was constructed that could control the door lock and the antitheft system and stream real-time images from the camera to the app.

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Development of a method for detecting trace metals in aqueous solutions based on the coordination chemistry of hexahydrotriazines

The Analyst ◽

10.1039/c5an00099h ◽

2015 ◽

Vol 140 (15) ◽

pp. 5184-5189 ◽

Cited By ~ 5

Author(s):

Rudy J. Wojtecki ◽

Alexander Y. Yuen ◽

Thomas G. Zimmerman ◽

Gavin O. Jones ◽

Hans W. Horn ◽

...

Keyword(s):

Heavy Metals ◽

Coordination Chemistry ◽

Trace Metals ◽

Aqueous Solutions ◽

Detection System ◽

Low Cost ◽

System P ◽

Chemical Indicator

The detection of trace amounts (<10 ppb) of heavy metals in aqueous solutions is described using hexahydrotriazines as a chemical indicator and a low cost fluorimeter-based detection system.

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Towards Finding the Optimum Position in the Visual Field for a Head Worn Display Used for Task Guidance with Non-registered Graphics

Proceedings of the ACM on Interactive Mobile Wearable and Ubiquitous Technologies ◽

10.1145/3448091 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1-26

Author(s):

Georgianna Lin ◽

Malcolm Haynes ◽

Sarthak Srinivas ◽

Pramod Kotipalli ◽

Thad Starner

Keyword(s):

Visual Field ◽

Order Picking ◽

Field Of View ◽

Line Of Sight ◽

Single Task ◽

Horizontal Field ◽

Optimum Position ◽

Preference Task ◽

Task Efficiency ◽

Task Guidance

Where should a HWD be placed in a user's visual field? We present two studies that compare comfort, preference, task efficiency and accuracy for various HWD positions. The first study offsets a 9.2° horizontal field-of-view (FOV) display temporally (toward the ear) from 0° to 30° in 10° steps. 30° proves too uncomfortable while 10° is the most preferred position for a simple button-pushing game, corroborating results from previous single-task reading experiments. The second experiment uses a Magic Leap One to compare 10° x 10° FOV interfaces centered at line-of-sight, temporally offset 15° (center-right), inferiorly offset 15° (bottom-center), and offset in both directions (bottom-right) for an order picking task. The bottom-right position proved worst in terms of accuracy and several subjective metrics when compared to the line-of-sight position.

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Design of a low-cost detection system for laser-induced plasma spectroscopy

Review of Scientific Instruments ◽

10.1063/1.1149953 ◽

1999 ◽

Vol 70 (9) ◽

pp. 3519-3522 ◽

Cited By ~ 12

Author(s):

R. E. Neuhauser ◽

B. Ferstl ◽

C. Haisch ◽

U. Panne ◽

R. Niessner

Keyword(s):

Detection System ◽

Low Cost ◽

Plasma Spectroscopy ◽

Laser Induced Plasma

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The Hardware Design and Implementation of Liquid Level Detection System for Lead-Acid Battery

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.860-863.2850 ◽

2013 ◽

Vol 860-863 ◽

pp. 2850-2854 ◽

Cited By ~ 1

Author(s):

Ya Jun Bi ◽

Hong Fei Li

Keyword(s):

Detection System ◽

Low Cost ◽

Liquid Level ◽

Lead Acid Battery ◽

Infrared Transmission ◽

Wireless Data ◽

Linear Ccd ◽

Infrared Technology ◽

Liquid Level Detection ◽

Lead Acid

The hardware structure of a liquid level detection system for lead-acid battery was briefly introduced. The system adopts AT89C51 MCU as host module, combined with display storage, extended storage and the watch dog technology. The slave module adopts AT89C2051 MCU, which driver the linear CCD to realize non-contact measurement in acidic and corrosive conditions. The infrared transmission module uses RS-232 serial-to-infrared technology to realize wireless data delivery. The damage due to sensor corrosion could be avoided in this system. Compared with other similar equipments, this system has the advantages of simple structure, small volume, low cost, high measure precision and convenient maintenance.

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Design of Mechaless LiDAR Optical System With Large FOV Using Liquid Lens and Fisheye Lens

ASME-JSME 2018 Joint International Conference on Information Storage and Processing Systems and Micromechatronics for Information and Precision Equipment ◽

10.1115/isps-mipe2018-8517 ◽

2018 ◽

Author(s):

Hyun Choi ◽

Wan-Chin Kim

Keyword(s):

Low Cost ◽

Autonomous Driving ◽

Voltage Regulation ◽

Field Of View ◽

Fisheye Lens ◽

Liquid Lens ◽

Fine Spatial Resolution ◽

Flash Lidar ◽

Optical Phased Array ◽

Measurable Distance

Mechaless LiDAR technology, which does not have a mechanical drive part, has been actively studied in order to increase the reliability of the LiDAR device at low cost and drive environment in order to more actively apply LiDAR technology to autonomous driving. Mechaless LiDAR technology, which has been mainly studied recently, includes 3D Flash LiDAR technology, MEMS mirror utilization method, and OPA (Optical Phased Array). However, these methods have not been developed rapidly as a key technology for achieving autonomous driving due to low stability of driving environment or remarkably low measurable distance and FOV (field of view) compared with mechanical LiDAR. In this study, we investigated the improvement of FOV by using a flux-deflecting liquid lens and a fisheye lens that can achieve fine spatial resolution through continuous voltage regulation. Based on the initial design results, it was examined that the FOV can be secured to 80 ° or more by utilizing a relatively simple fisheye lens composed of only spherical lenses.

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