Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Zener Diodes01:16

Zener Diodes

1.2K
Zener diodes are specialized semiconductor devices designed to operate in the reverse breakdown region, where they allow current to flow into the cathode, making it positive relative to the anode. This reverse operation distinguishes Zener diodes from conventional diodes and enables their use in various applications, most notably as voltage regulators. One of the defining characteristics of Zener diodes is their nearly vertical I-V (current-voltage) characteristic curve above a certain...
1.2K
The Ideal Diode01:15

The Ideal Diode

2.2K
A diode is a semiconductor device that allows current to flow in one direction only, making it a crucial component in electronic circuits for controlling the direction of current flow. An ideal diode is a simplified version of a real diode used to understand how diodes work in circuits. It possesses two terminals: the positive anode and the cathode, which is negative. When a positive voltage is applied to the anode relative to the cathode, the diode is in a forward-biased state, allowing...
2.2K
Diode: Forward bias01:20

Diode: Forward bias

2.2K
In semiconductor devices, diodes play a crucial role in directing current flow, and its operation is primarily categorized into forward bias and reverse bias. A diode is said to be forward-biased when its p-type region is connected to the positive terminal of a battery and its n-type region is linked to the negative terminal. This configuration reduces the potential barrier within the diode, allowing current to flow easily from the p to the n-type region.
The behavior of a diode in forward bias...
2.2K
Modeling of Diode Forward Characteristics01:19

Modeling of Diode Forward Characteristics

1.1K
Understanding the behavior of diodes when forward-biased is a fundamental aspect of electronic circuit design and analysis. This analysis primarily utilizes two models: the exponential diode model and the constant-voltage-drop model. The exponential model comes into play when the source voltage exceeds 0.5 volts, pushing the diode current to rise exponentially above the saturation current. This relationship is graphically depicted in the current-voltage (I-V) curve, illustrating the diode's...
1.1K
Diode: Reverse bias01:14

Diode: Reverse bias

1.9K
A diode is reverse-biased when the positive terminal of an external voltage source is connected to the n-type material and the negative terminal to the p-type material. This configuration opposes the natural direction of current flow through the diode, effectively increasing the width of the depletion region and the barrier potential. The reverse bias condition produces a minimal leakage current, primarily due to minority charge carriers. This leakage becomes significant when the reverse...
1.9K
Small-signal Diode Model01:18

Small-signal Diode Model

1.6K
In analyzing the behavior of diodes in circuits, the relationship between the current through a diode and the voltage across it is of particular interest, especially when considering the effect of a direct current (DC) bias voltage. When applied, this DC bias influences the diode's operating point, known as the Q point, around which the current-voltage (I-V) characteristic of the diode exhibits exponential behavior. Introducing a small, time-varying signal on top of this bias aids in examining...
1.6K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Central Nervous System Embryonal Tumour With PLAGL Amplification Lacking Typical Embryonal Morphology: Diagnostic Pitfall in a Paediatric Case.

Neuropathology and applied neurobiology·2026
Same author

Single-cell analyses identify the ginseng embryonic protoderm as a native compartment for high-efficiency ginsenoside production.

Nature communications·2026
Same author

Hypoglycemic Encephalopathy Caused by Insulinoma With Reversible High Signals in the White Matter on Diffusion-Weighted MRI: A Case Report.

Case reports in radiology·2026
Same author

Suppressing catastrophic forgetting in deep-learning-based imaging through scattering media.

Applied optics·2026
Same author

Noninvasive wavelength estimation through scattering media using recovered point-spread functions.

Applied optics·2026
Same author

Reversible Lesions of the Genu of the Corpus Callosum and White Matter Detected by MRI in a Neonate With Apnea: A Case Report.

Cureus·2026
Same journal

Segmentation-guided photon pooling enables robust single-cell analysis and fast fluorescence lifetime imaging microscopy.

Journal of biomedical optics·2026
Same journal

Method of spatial scanning of modulated laser radiation for outline imaging of interphalangeal joints.

Journal of biomedical optics·2026
Same journal

Multimodal optical imaging for the assessment of the teratogenic effects of ethanol on zebrafish development.

Journal of biomedical optics·2026
Same journal

Fluorescence properties of collagen types I-V: a comprehensive study of spectral and lifetime characteristics.

Journal of biomedical optics·2026
Same journal

Spectral dependence of lipofuscin fluorescence lifetimes revealed by FLIM with a superconducting nanowire single-photon detector.

Journal of biomedical optics·2026
Same journal

Building the future of biophotonics through experiential education and seasonal schools.

Journal of biomedical optics·2026
See all related articles

Related Experiment Video

Updated: Feb 4, 2026

Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes
07:44

Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes

Published on: November 16, 2018

9.4K

Mobile-phone-based Rheinberg microscope with a light-emitting diode array.

Yuma Ogasawara1, Ryo Sugimoto1, Ryoji Maruyama1

  • 1Ritsumeikan University, College of Science and Engineering, Department of Electrical and Electronic, Japan.

Journal of Biomedical Optics
|September 25, 2018
PubMed
Summary
This summary is machine-generated.

A new mobile phone microscope uses a light-emitting diode (LED) array for flexible illumination, enabling high-contrast imaging of living cells and chromatic structures in field studies.

Keywords:
Rheinberg illuminationbright-field imagedark-field imagedifferential phase contrast imagelight-emitting diode array microscopyportable microscopesmartphone

More Related Videos

Optimizing Photoneuromodulation Techniques to Evaluate the Role of Green Light-Emitting Diodes in Pain Management
09:03

Optimizing Photoneuromodulation Techniques to Evaluate the Role of Green Light-Emitting Diodes in Pain Management

Published on: March 28, 2025

1.1K
An In-House-Built and Light-Emitting-Diode-Based Photodynamic Therapy Device for Enhancing Verteporfin Cytotoxicity in a 2D Cell Culture Model
11:04

An In-House-Built and Light-Emitting-Diode-Based Photodynamic Therapy Device for Enhancing Verteporfin Cytotoxicity in a 2D Cell Culture Model

Published on: January 13, 2023

3.7K

Related Experiment Videos

Last Updated: Feb 4, 2026

Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes
07:44

Production and Characterization of Vacuum Deposited Organic Light Emitting Diodes

Published on: November 16, 2018

9.4K
Optimizing Photoneuromodulation Techniques to Evaluate the Role of Green Light-Emitting Diodes in Pain Management
09:03

Optimizing Photoneuromodulation Techniques to Evaluate the Role of Green Light-Emitting Diodes in Pain Management

Published on: March 28, 2025

1.1K
An In-House-Built and Light-Emitting-Diode-Based Photodynamic Therapy Device for Enhancing Verteporfin Cytotoxicity in a 2D Cell Culture Model
11:04

An In-House-Built and Light-Emitting-Diode-Based Photodynamic Therapy Device for Enhancing Verteporfin Cytotoxicity in a 2D Cell Culture Model

Published on: January 13, 2023

3.7K

Area of Science:

  • Biomedical Engineering
  • Optical Microscopy
  • Mobile Health Technology

Background:

  • Portable and affordable microscopy is crucial for field studies.
  • Traditional microscopes require complex optical component changes for varied illumination.
  • Light-emitting diode (LED) array microscopes offer flexible illumination without hardware modification.

Purpose of the Study:

  • To develop a mobile-phone-based LED array microscope for multimodal imaging.
  • To demonstrate the capability of achieving various contrast techniques with a single optical setup.
  • To enable high-contrast imaging of biological samples, including living cells and chromatic structures.

Main Methods:

  • Utilized a mobile-phone platform integrated with a 37-LED array.
  • Implemented flexible illumination patterns for bright-field, dark-field, differential phase-contrast, and Rheinberg illuminations.
  • Employed color combinations in Rheinberg illumination for enhanced contrast of chromatic structures.

Main Results:

  • Achieved high-contrast imaging of living cells using the developed microscope.
  • Successfully visualized living chromatic structures with adjustable contrast levels.
  • Demonstrated the versatility of the LED array for multimodal imaging capabilities.

Conclusions:

  • The mobile-phone-based LED array microscope provides a cost-effective and versatile solution for advanced microscopy.
  • This technology facilitates high-contrast imaging in diverse field settings.
  • It is expected to be a foundational tool for modern field-based biological studies.