Patent Application
20050080354
This invention generally relates to measurement of the body temperature of a human with an ear thermometer. More particularly, this invention relates to an ear thermometer with an illumination feature.
Infrared thermometers for measuring the temperature of the human body are in wide-spread use. Such thermometers are typically inserted partially into the ear canal to measure the temperature in the interior of the ear, and, hence, the body temperature.
Some prior art patents disclose the use of illumination in an ear instrument. U.S. Pat. No. 4,494,881 to Everest discloses a sighting system for an infrared thermometer that provides a visible light beam that is parallel with path of the infrared rays through the optics of this system. The optics in this system are complex and relatively expensive, such as Cassegrainian lens systems, Fresnel lenses, beam splitters and the like. This system also has the undesirable effects of introducing visible light energy into the ear canal, which can interfere with accurately measuring the temperature with infrared techniques. Furthermore, the visible light for guiding the probe of the infrared thermometer into the ear canal must be seen from the side since the body or housing of the thermometer blocks any direct view into the ear canal as the probe nears the ear. Thus, if the light beam of Everest is directly into the ear canal, it may be difficult to see it from the side. Thus, use of a narrow and apparently collimated visible light beam directly into the ear canal, as proposed by Everest, is not an effective means of assisting the insertion of the probe of the thermometer into the ear canal.
U.S. Pat. No. 5,209,757 to Klug et al. teaches an illuminated ear cleaning device with an incandescent light bulb at the end of a tube near a cleaning tip. However, this technique cannot be applied to an infrared thermometer because the light bulb would block the end of the probe through which infrared radiation needs to be received by the thermometer. Moreover, if the radiation emitted by the light bulb is in the path of the infrared radiation from the ear, inaccuracies would be introduced in measuring the infrared radiation.
Many persons, including medical personnel, prefer infrared ear thermometers over electronic oral thermometers because of the convenience and the rapid temperature measurement that the infrared ear thermometers offer. Typically, a hygienic plastic sleeve may be placed over the tip of the probe before each use of the thermometer, the probe itself may be disposable, or the tip of the probe can be cleaned with alcohol.
However, there is often a need to measure temperature with an ear thermometer when the room is dark, such as at nighttime or in rooms with poor ambient light levels. For example, it may be desirable to take the temperature of an infant, child or adult without disturbing their sleep, as by turning on lights in the room. But, without adequate light, it is also difficult to properly position the ear thermometer near the ear and into the ear canal of the person.
There is therefore a need for an ear thermometer with a light feature that provides enough illumination to properly position the thermometer in or near the ear, without flooding the room with light that may be annoying to the person.
It is therefore a general object of the present invention to provide an ear thermometer with an illumination feature to provide sufficient illumination to properly position the ear thermometer for insertion of the probe tip into the ear.
It is another object of the present invention to provide such an illumination feature that is integral with the ear thermometer and easy to use.
A further object of the present invention is to provide such an illumination feature for an ear thermometer that may be selected when desired or needed.
Yet another object of the present invention is to provide an illumination feature wherein the direction of the illumination is forward of the probe tip of the ear thermometer.
Another object of the present invention is to provide a divergent pattern of illumination from a light source for illuminating at least the area of the ear around the ear canal, and, preferably, the entire ear.
The present invention is directed to an improved ear thermometer with illumination to assist in inserting a probe of the thermometer into the ear canal of a human being. The thermometer has a housing that may consist of multiple housing portions. A display for displaying a measured temperature is disposed on a rear side of the housing. A tapered probe is disposed on the front side of the housing, typically at an oblique angle thereto. Preferably, the probe is also pivotally and/or rotationally mounted to the front side of the housing to permit some movement of the housing of the thermometer while the probe is inserted into the ear canal. A display is also disposed on the housing for displaying a measured temperature.
In accordance one aspect of the present invention, a light source is disposed on the housing to supply illumination in front of the tip of the probe to illuminate at least the area around the ear canal as the tip of the probe is being inserted therein. A separate switch is preferably disposed on the housing to control when the light source is actuated, thereby conserving battery power. The light source may include an incandescent lamp or one or more light emitting diodes (LEDs) of the bright type. The illumination provided by the light source is in the form of divergent rays to illuminate a substantial area of the ear, and preferably the entire ear.
In accordance with another aspect of the present invention, the light source may be disposed in a raised protrusion on the housing, such as at the top end thereof. The illumination from the light source is generally directed forwardly of the tip of the probe to illuminate the field in front thereof. An axis may be defined through the probe. At least some of the illumination provided by the light source will intersect with the axis in front of the tip of the probe.
The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with the further objects and advantages thereof, may best be understood by reference to the following description taken in conjunction with the accompanying drawings, in the several figures in which like reference numerals identify like elements, and in which:
Referring to the Figures, and particularly to
Display 28 may of the liquid crystal display (LCD) type and provide a variety of indicia for informing the user of the temperature measurements and of the operating modes. For example, it may have numerical indicia to numerically display a measured temperature and it may also have alpha indicia, such as an “L” to indicate that the measured temperature is below the normal temperature range such as below about 32° C. (89.6° F.), and an “H” to indicate that the measured temperature is above the normal temperature range such as about 43° C. (109.4° F.). Display 28 may also have indicia, such as “C” to indicate that the measured temperature is in degrees Celsius and “F” to indicate that the measured temperature is in degrees Fahrenheit. Additionally, display 28 may include an “M” to indicate that the displayed temperature is from memory. For example, when the thermometer 20 is first turned on, it is desirable to display the last measured temperature in case it was not previously recorded or to remind the user of the prior temperature.
As seen in
Preferably, as shown in
With reference to
In accordance with one aspect of the present invention, illumination is provided at or in front of the tip 39 of the probe 36 to assist in inserting probe 36 into a patient's ear canal to measure the patient's temperature. To this end, an elongated protrusion 40 is formed at or near the top of housing 21, such as at the top ends of housing portions 30 and 31. The location of the light source on the housing 21 is not critical and other locations may also be suitable, such as on the front housing portion 31 below the probe 36, on the sides of front housing portion 31, or the like. However, the top of the housing is preferred because this location generally provides a minimal shadow of the probe tip as the probe 36 is being inserted into the ear canal for thermometers of the type illustrated in
A light source 42-43 in the form of an incandescent lamp or one or more LEDs are contained in protrusion 40 and are oriented to provide divergent rays 41 of illumination toward and in front of the tip 39 of probe 36. Light source 42-43 thus provides an area of illumination in front of probe 36 to assist in inserting the probe into the patient's ear, especially in lower ambient lighting circumstances, such as in the evening hours or in rooms with low ambient light levels. This also obviates the need to turn on other lighting in the room, which may undesirably disturb the patient.
At least some of the rays 41 of illumination provided by the light source 42-43 will generally intersect with the axis 38 of probe 36 forwardly of the tip 39 of probe 36. If LEDs are used for the light source 42-43, the LEDs are preferably of the bright variety to provide sufficient illumination in the darkest environments. Of course, light source 42-43 is only activated to provide illumination when illumination switch 26 is actuated to the on position, which saves on current drain of the batteries and extends normal battery life.
The electronic circuitry 50 for operating the thermometer 20 is shown in the schematic diagram of
Positive operating power, such as from a DC battery, is received at terminals VCC 58 for operation of microcontroller 52 and its associated circuitry. Similarly, negative operating power is received at terminal VSS 59. Capacitors 60 and 61 filter the power provided to microcontroller 52. A jumper 62, when closed, sets the circuitry 50 in the calibration mode. When jumper 62 is open, the circuitry 50 is set for the normal temperature measuring mode. A jumper 63, when closed, establishes temperature measurement in the Fahrenheit mode. If jumper 63 is open, temperature measurement will be in the Celsius mode. A switch 64 provides a scan/memory function.
Some of the indicated terminals connect to other terminals in the schematic diagram of
A plurality of resistors 80-87 interface microcontroller 52 with terminals 90-91 that connect to a thermopile 95 and with terminals 92-93 that connect to a temperature sensing thermistor 96. Terminal 91 is connected to the positive terminal of thermopile 95. The thermopile 95 typically measures the temperature of the patient by developing a signal that is proportional to the amount of incident infrared radiation from the ear canal. The thermistor 96 typically measures the ambient temperature. Certain of resistors 80-87 thus couple thermopile 95 to respective terminals of microcontroller 52. Certain of resistors 80-87 similarly couple signals from thermistor 96, which are representative of the measured temperature, back to microcontroller 52 for further analysis of the measured temperature. Switch 88 may be used to check any offset in the temperature measurements, especially during the calibration procedures. It is therefore not accessed by the user during normal operation of thermometer 20.
Certain pins of microcontroller 52 are dedicated to provide information to display 28 and to also provide control signals to display 28. Microcontroller pins 49-61 provide the SEG13-SEG1 signals to display 28, and pins 62-provide 64 the COM1-COM3 signals to display 28. Microcontroller is thus able to supply information and control signals to display 28 to display the measured temperature and the various operating modes and other conditions, including “L” for a low out-of-range temperature, “H” for a high out-of-range temperature and “M” for a temperature previously stored in memory.
It will be understood that the embodiments of the present invention that have been described are illustrative of some of the applications of the principles of the present invention. Various changes and modifications may be made by those skilled in the art without departing from the true spirit and scope of the invention.
