Panasonic Corporation

Tomoaki Ieda

Hiroyuki Sasai

Kazutoshi Hase

Keisuke Kinoshita

Hideo Yasumoto

An optical emitting module includes a light-emitting device that emits light, and a lens member having a refracting surface configured to refract light emitted from the light-emitting device and to emit refracted light. The lens member is configured such that, when the angle of a light beam emitted from the lens member with respect to a principal light axis is &#x3b8;, a light beam with the maximum emission angle &#x3b8;from the lens member is emitted from the refracting surface in the vicinity of a point where the refracting surface and the principal light axis cross each other. With this configuration, even when the light-emitting surface of a light source is large, it is possible to suppress the spread of emergent light from the lens member, obtaining a light intensity distribution with high uniformity.

Optical emitting module

Provided is an optical space transmitter and an optical space transmission method, for wavelength-multiplexed light, capable of obtaining a wavelength-multiplexed signal by multiplexing optical signals having a plurality of wavelengths with a simple configuration and without requiring highly precise adjustment for optical axes and enhancing safety for a human body. The transmitter has a configuration for which light sources for outputting signal lights having wavelengths different from each other are arranged so as to irradiate an approximately identical portion of a diffusion plate, a diffuse light outputted from the diffusion plate is converted, by a radiation lens, into a light traveling with an angle suitable for transmission in a free space, and the converted light is passed out to the free space.

Optical space transmitter and optical space transmission method for wavelength-multiplexed light

A peaking current generating section generates a spire-shaped peaking current that is in synchronism with the transitions of the digital signal, at the rising edge and the falling edge. A light emitting element driving section produces a driving current obtained by combining together a signal amplitude current according to the amplitude of the digital signal and the peaking current. Then, the light emitting element driving section drives a light emitting element by using the driving current. A signal analysis section analyzes the digital signal so as to set a control signal based on the pulse width of the digital signal. A clipping section clips the peaking current of the driving current according to the control signal set by the signal analysis section.

Optical transmitter circuit

A first peaking current generating section generates a first peaking current in synchronism with the transitions of a digital signal, being positive at the rising edge and negative at the falling edge. A second peaking current generating section generates a second peaking current in synchronism with the transitions of the digital signal, being negative at the rising edge and positive at the falling edge. A first light emitting element driving section produces a first driving current obtained by combining together a signal amplitude current according to the amplitude of the digital signal and a first peaking current. A second light emitting element driving section produces a second driving current obtained by combining together the signal amplitude current according to the amplitude of the digital signal and a second peaking current. Then, the first and second light emitting element driving sections and drive the light emitting element by using a driving current obtained by subtracting the first driving current from the second driving current.

A plurality of first refraction surfacesand a plurality of second refraction surfacesare alternately provided on an emission surface of a lens elementso as to form concentric circles each having an optical axisat the center thereof, and having diameters different from each other, and a light reflected by a plurality of reflection surfacesprovided on an incident surface of the lens element so as to form concentric circuits each having the optical axisat the center thereof and having diameters different from each other, is refracted and emitted by the plurality of second refraction surfacesat desired angles. Therefore, it is possible to enhance efficiency and an emission intensity, and reduce variations in brightness of an emitted light without increasing the diameter of the lens element, thereby realizing a light emitting moduleenabling advantageous performance.

Light emitting module and light receiving module

An optical transmission apparatus is provided in which high optical output power is secured in an optical transmitter, the fine adjustment of the optical axis is unnecessary, and the propagation range of the optical output signal can be adaptively changed. A diffusing liquid lens includes a first liquid and a second liquid containing a scattering material that scatters light, and the curvature of the boundary surface between the first and the second liquids is changed according to the control voltage applied from a controlling unit. A first optical signal outputted from a light emitting device is diffused in the first liquid, and emitted as a second optical signal having a spread angle corresponding to the curvature of the boundary surface and a substantially uniform radiant intensity distribution.

Liquid lens optical transmitter system

A space optical transmission apparatus is provided which achieves high-speed simultaneous space optical transmission with respect to a plurality of terminals. In the space optical transmission apparatus, a light receiving section receives an optical signal from a terminal. A control section estimates how much optical axes of a master station and the terminal are deviated from each other, based on the received optical signal. The control section selects one of a plurality of light sources which requires a smallest amount of shift of an optical axis thereof, based on the estimated optical axis deviation amount, so as to communicate with the terminal.

Growing community of inventors

Osaka, Japan

Tomoaki Ieda