Illumination – Light source or light source support and luminescent material
Reexamination Certificate
1998-11-25
2003-02-11
O'Shea, Sandra (Department: 2875)
Illumination
Light source or light source support and luminescent material
C362S029000, C362S800000, C362S231000, C362S489000, C362S034000
Reexamination Certificate
active
06517213
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an indicator device, such as an industrial (especially manufacturing-industrial) indicator lamp, which guides a light from a light source to a predetermined indicating surface to make an optical indication entirely on the indicating surface, an illuminating device which guides the light from the light source to a light-projected surface to make an illumination entirely on the light-projected surface and an indicator device (LED bulb) consisting of an emitter body with light emitting diode (LED) elements mounted two-dimensionally and a dome-shaped cap member attached thereto.
2. Description of the Background Art
In order for a safe operation of an in-plant system and the like, it is necessary for an operator to always monitor the condition of machinery, facilities and the like while performing operation, control, management and handling over the machinery. For this reason, a control panel and the like in the plant are provided with an indicator lamp to indicate the condition of the system. The indicator lamp has a light-transmissible plate (inscription plate) with characters such as “ON”, “OFF”, “OPERATION” and “ALERT”, signs, pictures and the like. When the light source behind the inscription plate is turned on according to the operating condition of the system, an optical indication is made entirely on the indicating surface, being visually recognized by the operator. The indicator lamp may be provided in a variety of forms, and among typical forms are a unit indicator lamp for indicating a single information, a collective indicator lamp for indicating plural pieces of information and an illuminated push-button switch with indicator lamp having an additional function of operating the system, such as operation/stop.
In short, the indicator lamp is a device provided on a panel surface of the control panel to inform the operator of the system condition, and assumes a dominant position in a man-machine interface for a safe operation of the system by the operator.
Anyway, there is a request for color-coded representation in such an indicator lamp. Since a control panel and the like usually has a plurality of indicator lamps, if color-coding depending on purposes is made and information (characters, signs, signs and pictures) with coded colors is given, instead of information being monochromatically presented, the viewability of the indicator lamp can be improved.
In the today's light source available for the indicator lamp, however, the kind of colors of light emitted therefrom is limited and therefore there is a limit of color-coded representation.
Further, it is necessary to prevent the shape of an emitter in the light source (dots of an LED element and filament or bulb of an incandescent bulb) from being externally recognized so that the operator can easily recognize indication such as characters (what are represented by the characters).
Furthermore, a halogen lamp may be used as the light source to achieve a pure-white indicator lamp, but this causes a problem of short lifetime of the light source due to a great amount of heating values, so that it can not be applied to actual use as of today.
If the color of the indicator lamp in an on state (the color of indication light) and the color in an off state (its appearance color) are different, there arises a problem that the color of the indicator lamp in the on state can not be known from the color in the off state. If the color of the indicator lamp in the on state can not be known, especially in a case where a plurality of indicator lamps having plural kinds of colors different from one another are provided in the control panel and the like, it is not easy to recognize what color an indicator lamp in the off state will have in the on state and that makes it difficult to intuitively recognize what the indicator lamp informs with color information.
Though an indication color obtained by transmitting a light from the light source using an incandescent bulb through a milky-white plate has been conventionally called “white” in this art, the color temperature of the incandescent bulb can not be considered white, being much different from pure white obtained by the light source using a unit of red, green and blue LED elements or the halogen lamp, and the above request is not satisfied.
SUMMARY OF THE INVENTION
Objects of The Invention
The present invention is intended to solve the above problems in the prior-art indicator device and an object of the present invention is to provide an indicator device capable of making an optical indication with any colors.
Another object of the present invention is to provide an indicator device which allows high-order achievement in both highly-intensified indication and high diffusibility of light.
A further object of the present invention is to provide an indicator device and an illuminating device capable of eliminating variation in the amount of light on an indicating surface or a light-projected surface.
An yet object of the present invention is to provide an indicator device which achieves any-color indication light from a light emitted by a single-color light source and allows the color of the indicating surface in an on state of the light source (indication light) to be easily recognized from the color of the indicating surface in an off state of the light source with higher productivity and lower cost.
Still another object of the present invention is to provide an indicator device (LED bulb) capable of emitting a light of white or other delicate color which is difficult to emit with a single LED element.
Constitution and Action of The Invention
According to the present invention, an indicator device which makes an indication by illuminating a predetermined indicating surface comprises: a light source for emitting a light of a first wavelength; and a fluorescent plate provided between the light source and the indicating surface, for changing at least part of the light of the first wavelength projected thereto from the light source into a light (L
2
) of a second wavelength longer than the first wavelength and projecting the light of the second wavelength towards the indicating surface.
In the present invention, since the fluorescent plate provided between the light source and the indicating surface changes at least part of the light of the first wavelength projected thereto from the light source into the light of the second wavelength longer than the first wavelength and projects it towards the indicating surface, the color of the light of the second wavelength and the ratio of the light of the second wavelength projected from the fluorescent plate and the light of the first wavelength through the fluorescent plate can be easily changed only by changing the kind of the fluorescent plate to be used, and as a result indication lights of various colors for illuminating the indicating surface can be easily obtained from the single light of the first wavelength. Therefore, since the light source has only to be provided with one kind of light source for emitting the light of the first wavelength, it is possible to ensure higher productivity and lower cost as compared with, for example, a case of changing combination of kinds of the LED elements to be used according to the color of the indication light.
According to the present invention, the indicator device further comprises: a filter provided between the fluorescent plate and the indicating surface, for transmitting at least part of the light projected from the fluorescent plate towards the indicating surface, and in the indicator device, a color of a light through the filter to illuminating the indicating surface in an on state of the light source and an appearance color of the filter which substantially defines a color of the indicating surface in an off state of the light source are substantially identical or similar to each other.
In the present invention, since the light through the filter to illuminate the indicating surface when the light source i
Fujita Toshihiro
Mamiya Masaru
Nishihara Ikkan
Okamoto Akito
Tanabe Shinichi
IDEC Izumi Corporation
O'Shea Sandra
Ostrolenk Faber Gerb & Soffen, LLP
Ton Anabel
LandOfFree
Indicator device and illumination device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Indicator device and illumination device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Indicator device and illumination device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3124299