Effects of a Cylindrical Cavity on the Etendue of a Light Source

  title={Effects of a Cylindrical Cavity on the Etendue of a Light Source},
  author={Ui-Hyung Lee and Young‐gu Ju},
  journal={Japanese Journal of Applied Physics},
This paper proposes that the cylindrical cavity around a circular light source can decrease the divergence angle without changing the emission energy and source size. This result can provide a way to reduce the etendue of the light source by scrambling the rays inside the cavity with a lossless scattering surface. The experiment demonstrated that the metallic cavity around the surface source reduced the divergence angle. However, the metallic surface also absorbed quite a large portion of the… 
1 Citations
Uniform line sources based on a holed cavity and a laser
A line source consisting of a laser, a fiber-like waveguide, phosphors, and a holed cavity is suggested. The simulation demonstrated that this type of line source achieved small emission thickness


Light recycling in solid state devices
The idea of light recycling is rather simple. Assume that part of the light emitted by a light source is returned to the light source itself. If the light source does not completely absorb this light
Homogeneous LED-illumination using microlens arrays
Efficient homogeneous illumination of rectangular or circular areas with LEDs is a promising application for doublesided microlens arrays. Such illumination schemes employ a primary optics - which
Light Collection within the Framework of Geometrical Optics
The problem of light collection is examined from first principles within the framework of geometrical optics. From the outset, we distinguish between light collection and the usual theory of image
Field Guide to Geometrical Optics
This Field Guide derives from the treatment of geometrical optics that has evolved from both the undergraduate and graduate programs at the Optical Sciences Center at the University of Arizona. The
61.5: LED‐Based Light‐Recycling Light Sources for Projection Displays
LED‐based light sources utilizing novel light‐recycling cavities have been developed that have small output etendue. A portion of the light emitted by the LED source is recycled back to the LEDs to
Design Methodology for High Brightness Projectors
A taxonomy of the techniques that can be used to increase the brightness of LED-based projection displays shows that, in etendue-limited systems, the perceived brightness depends on the system Etendue limit, the efficiency of the light engine, and the source luminance.
25.3: LED Array with Recycling for High‐Power Projector Applications
LEDs are still not bright enough, compared to arc lamps, for high power projector applications. For high power applications, multiple LEDs are required to increase the total light output with the
P-GaN/N-InGaN/N-GaN Double-Heterostructure Blue-Light-Emitting Diodes
P-GaN/n-InGaN/n-GaN double-heterostructure (DH) blue-light-emitting diodes (LEDs) were fabricated successfully for the first time. The output power was 125 µW and the external quantum efficiency was
Aberrations of the symmetrical optical system
Only for you today! Discover your favourite aberrations of the symmetrical optical system book right here by downloading and getting the soft file of the book. This is not your time to traditionally
Hole Compensation Mechanism of P-Type GaN Films
Low-resistivity p-type GaN films, which were obtained by N2-ambient thermal annealing or low-energy electron-beam irradiation (LEEBI) treatment, showed a resistivity as high as 1×106 Ωcm after