Patent Application
20080023625
Further advantages, details and features will become evident from the following description of one exemplary embodiment, on the basis of an example.
In the figures:
The light curing appliance 10 illustrated in
The light curing appliance 10 can be placed in a base station 18. The light curing appliance has rechargeable batteries which are automatically charged, when the state of charge requires this, when it is placed in the base station 18.
The light curing appliance can be switched on by means of a push-button. switch 20 which is arranged in a manner known per se on the inner upper face of the pistol grip 16. In this state, light is emitted from a schematically indicated light source 22, and part of it is passed via a reflector to a light guide apparatus 24.
The light guide apparatus 24 is composed of a tube in which an optical waveguide is guided. The front end of the light guide apparatus 24 is angled in order to provide easy access to points which are difficult to reach, and at which material to be polymerized must be subjected to light curing.
The light guide apparatus ends at the front at a light outlet area 30 which, for example, can also be provided with a transparent cover or possibly a convergent lens.
The light source 22 can be switched on by means of the push-button switch 20 and, during operations the light outlet area 30 is held in the mouth of the patient directly at the point at which the dental restoration material that is to be polymerized is located. The indication apparatus 14 signals when the polymerization process has been completed.
After completion of the curing process, the hand piece of the light curing appliance 10 is normally placed back in the base station 18, where rechargeable batteries which are accommodated in or on the pistol grip 16 of the light curing appliance are charged via electrical contacts.
A further indication apparatus 32 and/or the indication apparatus 14 also indicate/indicates the state of charge of the rechargeable batteries, and light curing is allowed only when the remaining energy in the rechargeable batteries is likewise sufficient for the curing process.
The invention provides for the design of a light measurement apparatus, to be precise preferably one which is integrated directly in the base station 18. The light measurement apparatus 34 is used to check whether the optical characteristics of the light curing appliance 10 are also sufficient—that is to say irrespective of the state of charge of the rechargeable batteries. By way of example, a reduction in the light output from the light source, dirt on the reflectors which are installed there, an accidentally inclined position of the light guide apparatus, or dirt on or other damage to the light outlet area 30 can result in a reduction of the light power, even if the check of the electrical values in the light curing appliance leads to the expectation that there is no malfunction.
However, according to the invention, this can be checked by means of the light measurement apparatus 34. The light measurement apparatus 34 has a light sensor arrangement 36 which extends underneath a horizontal surface of the base station 18. The housing of the base station 18 has a transparent cover 38 so that the light sensors are protected against dirt.
The light sensor arrangement has a large number of light sensors, with the light sensors 40a, 40b, 4Cc, 40d, 40e, 40f, 40g, 40h, and 40i being illustrated in
Furthermore, the light measurement apparatus 34 has a stop 42 which acts as a stop for the light guide apparatus 24, the stop being disposed immediately adjacent to an end of the light sensor arrangement 36. The light guide apparatus 24 is additionally illustrated in
The output signal for all of the light sensors is detected, and is supplied to an evaluation circuit, which is not illustrated. The evaluation circuit detects both the intensity of the respectively emitted radiation and any light sensor—in this case after the light sensor 40e—from which there is no illumination. Both the diameter of the light outlet area 30 and the strength of the indicated light radiation are determined from these two detected measured values—in each case in a distribution transversely across the light outlet area 30—and are indicated on the indication apparatus 32.
As can be seen from
The cover 38 may be covered by a translucent or transparent filter which essentially compensates for the spectral sensitivity of the sensors in the light sensor arrangement. In addition, a protective shutter may be installed on either the filter or the cover, which leaves free an area in the form of a slot above the light sensor arrangement, and covers areas to the side of this area. The thickness of the cover—and likewise of the filter which is formed on it—is quite small, for example around one millimeter. Tests have shown that the beam widening of the light guide apparatuses is uniform in this region, so that the actual diameter of the light outlet area can be determined directly, based on the distance between the light outlet area and the sensors being constant.
The light sensors 40a, 40b, 4Cc, 40d, . . . 40o extend closely adjacent to one another and in practice form a type of bar. While 15 light sensors are shown in
A discriminator may be connected to one light sensor (40a, 40b, 40c, . . . ), which discriminator emits an ON signal when the detected amount of light is above a predetermined threshold value, and emits an OFF signal when the amount of light is below the threshold value.
A further feature of the invention is that the number of sensors illuminated by the light guide apparatus are determined by an evaluation circuit, and the average amount of light applied to the sensors is calculated in order to calculate the light power per unit area of a light source. The light sensor arrangement measures not only the amount of light emitted per unit area from the light outlet area but also the diameter of the light outlet area.
It is self-evident that, instead of this, the light measurement apparatus 34 according to the invention may also be installed at any other desired point. For example, one central light measurement apparatus can also be provided for a large number of light curing appliances 10, and it is also possible to code the respective hand piece, so that the light measurement apparatus detects which hand piece is currently being measured. In this refinement, the measured values are preferably detected and stored, and any deterioration in the optical characteristics is used to determine when it can thus be expected that the light curing appliance requires a general overhaul.
While a preferred form of this invention has been described above and shown in the accompanying drawings, it should be understood that applicant does not intend to be limited to the particular details described above and illustrated in the accompanying drawings, but intends to be limited only to the scope of the invention as defined by the following claims. In this regard, the term “means for” as used in the claims is intended to include not only the designs illustrated in the drawings of this application and the equivalent designs discussed in the text, but it is also intended to cover other equivalents now known to those skilled in the art, or those equivalents which may become known to those skilled in the art in the future.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2006 035 657.8 | Jul 2006 | DE | national |
This application claims foreign priority benefits under 35 U.S.C. §119(a)-(d) from German patent application ser. no. 10 2006 035 657.8 filed Jul. 31, 2006. In addition, this application claims the benefit under 35 U.S.C. §119(e) of U.S. provisional patent application Ser. No. 60/880,764 filed Jan. 17, 2007.
| Number | Date | Country | |
|---|---|---|---|
| 60880764 | Jan 2007 | US |
