Surgical light and method for operating a surgical light

A surgical lamp for illuminating a surgical field on a human body is provided. The surgical lamp comprises a control device (4), a lamp body (1) comprising several illuminants (3) with one respective light ray (I, II, II′) directed to the surgical field, and a 3D sensor (6) for detecting a spatial position of at least one object, and a device for switching on and off and dimming the illuminants (3), wherein the control device (4) controls the devices for switching on and off and dimming the illuminants (3), the 3D sensor (6) detects the spatial positon of the at least one object and transmits corresponding data to the control device (4), and the control device (4) is configured to control the illuminants (3) according to the spatial position of the at least one object.

CROSS REFERENCES TO RELATED APPLICATIONS

This application is a U.S. national phase of PCT/EP2015/075647, filed on Nov. 3, 2015, which claims the benefit of and priority to German Patent Application Serial No. 102014222794.1, filed Nov. 7. 2014, both of which are incorporated herein by this reference in their entirety.

The invention relates to a surgical lamp and a method for operating a surgical lamp, in particular, a surgical lamp having automatic setting possibilities for a light field, and a method for illuminating a surgical field on a human body by this surgical lamp.

Document U.S. Pat. No. 6,880,957 B2 shows a surgical lamp, whereby each light source is equipped with a sensor. The sensor recognizes an obstacle only in the beam path of the respective light source and dims this light source in order to prevent shadowing by the obstacle.

However, thereby, merely a current position of the obstacle, namely a presence within the respective beam path, is evaluated. Thus, a changing shadowing of the surgical field cannot be predetermined and an action in advance is not possible.

Thus far, pure distance measuring devices are deployed for a distance measurement between a lamp body of the surgical lamp and the surgical field and additional specific sensors are used for further sensor based application, as e.g. the setting of a focus situations and/or light field dimensions or a gesture control.

The invention is based on the object to provide a surgical lamp providing the precondition of anticipatorily preventing or reducing shadowing and providing further operation and functional possibilities in an economical manner.

The object is achieve by a surgical lamp according to claim1and a method according to claim14. Further developments of the invention are subject-matters of the dependent claims.

By a provision of a 3D sensor at a lamp body of a surgical lamp, a spatial position of an object between the lamp body and a surgical field as well as a distance of the surgical field from the lamp body as the position can be detected.

FIG. 1shows a lamp body1of a surgical lamp. The lamp body is fixed by a suspension device (not shown) to e.g. at a room ceiling via a pivot joint2in a manner pivotable in all directions.

The lamp body1is provided with several illuminants3. The illuminants3are located within the lamp body1and, in the alignment of the lamp body1shown inFIG. 1, radiate light in a respective light ray downwardly. The light rays are directed to a surgical field on a human body in order to illuminate this. Only four of a plurality of the illuminants3are illustrated here. The illuminants3are carried out as LEDs here and they are basically distributed across an entire light escape area at the lamp body1.

Further, the surgical lamp comprises a control device4in the lamp body1or, alternatively, at another suitable position, e.g. at a ceiling fixation.

Here, the surgical lamp is provided with operating elements5at the lamp body1, wherein the operating elements5can also be provided at the suspension device or at a wall panel (not shown).

The illuminants3and the operating elements5are connected to the control device4. The control device4controls the illuminants via a device (not shown) for switching on and off and dimming the illuminants according to settings at the operating elements5. By the operating elements5, a setting of an intensity of the light radiated by the illuminants3, i.e. a brightness in the surgical field, and of a diameter of a light field generated by the illuminants3in the surgical field are possible. Optionally, further setting possibilities, e.g. a color temperature of the radiated light, are possible.

At the lamp body1, a 3D sensor6for detecting a spatial position of objects, as e.g. parts of the body of the surgical personnel, surgical apparatuses or a body of a patient, or of motions of the objects is arranged. The 3D sensor6is connected to the control device4and transmits data according to the detected objects to the control device4. The control device4evaluates the data of the 3D sensor6and controls the illuminants3according to the position and the motion of the objects.

Alternatively, the 3D sensor6can already evaluate the position of the objects and transmits accordingly processed data to the control device4. In a further alterative, the data of the 3D sensor6are processed up to a defined degree by this and, then, they are finally processed by the control device4. This is then beneficial if data, e.g. having the same format characteristic, are transferred from different sources to the control device4. In a further alternative embodiment, the 3D sensor6transfers data of different processing stages if, as described later, these are differently evaluated for different functionalities. In view of functionalities of the surgical lamp based on 3D sensor data, several control devices4are optionally provided.

Optionally, the 3D sensor6additionally detects a size of the detected objects. From the data concerning the size, the spatial position and the motion of the object, the control device4controls the illuminants3such that light rays impinging on a detected object between the lamp body1and the surgical field are dimmed or switched off. Thereby, shadowing by the object is reduced or prevented. The illuminants3, the light rays of which do not impinge on the object but are directed past the object to the light field, are then operated with increased performance in order to maintain an illuminance, i.e. the brightness, in the surgical field at least almost constant despite the object between the lamp body1and the surgical field. The larger the object is the higher is e.g. the performance with which the illuminants3, the light rays of which do not impinge on the object, are operated. Optionally, the size of the object is also associated with its measured distance. It is assumed that the shadowing is slight upon a small distance to the lamp body1than upon objects with a large distance to the lamp body1or to the 3D sensor when focusing the light rays to the surgical field.

Thereto, a space filled by the light ray for each of the illuminants3is stored in a memory area of the control device4. Under consideration of a distance information, the space can optionally be divided in further portions. When the object between the lamp body1and the surgical field is located at least partially in the space of the light ray or in one of the portions of the space of a certain illuminant3, this illuminant3is dimmed or switched off. The amount of the dimming is determined by a proportion of a cross section of the light ray occupied by the object. The illuminants3adjacent to this certain illuminant3are then operated with increased performance.

Optionally, a contour of the detected object is also detected. In the memory area of the control device4, different contours of the objects are stored. The illuminants3are then differently controlled depending on the contour of the detected object, therefore per a kind of the object. Thereby, a certain area of the surgical field can be illuminated with an increased illuminance for e.g. a certain type of surgical instrument. Upon recognizing e.g. a tissue retractor, the periphery of the surgical field is illuminated in an increased manner compared to other areas or, alternatively, a shadowing is reduced or prevented. However, when recognizing a scalpel, the center of the surgical field is illuminated in an increased manner than other areas or, alternatively, shadowing is reduced or prevented there. Therefore, the position into which the object will move and, therefore, in which manner the illuminants3will be controlled are predicted by the control device4due to the contour.

In turn as an option, the control device4determines a position into which the object will move, therefore, in which it will be located at a certain subsequent point of time, from a spatial position of the detected object and its motion, namely its direction and/or its velocity and/or its acceleration. Thereby, it is possible that the control device4prevents shadowing in real-time without a delay by a response time of the 3D sensor, the control device4and the illuminants3.

Further, the control device4is optionally also configured to detect an object being located between the lamp body1and the surgical field outside of a light cone generated by the light rays, or being located within in a predetermined position. The control device4then determines the manner to control the illuminants3from a direction and/or trajectory and/or a velocity and/or an acceleration of a motion of the detected object. Thereby, it is possible to control the illuminants3by the control device4, e.g. by a gesture control by means of a hand movement, in order to dim the surgical lamp or to change the light field diameter.

The light field diameter is defined such that an illuminance of 10% of an illuminance in the center of the light field exists on this diameter.

The allocation of detected objects to functions to be controlled can optionally happen via a space partition and/or specific distinctive features/characteristics. Further, by the detected objects according to the space partition, also switching between a prevention of shadowing and a gesture control can happen. Upon the space partition, different portions in direction of the light rays can be defined. For example, in the near-field of the lamp body, in particular in a region where usually the heads of the surgical personnel are located, detected objects are used for the prevention of the shadowing. In a middle region where usually the hands of the surgical personnel are located, the objects and their motions are understood as gestures for the gesture control. In a region on or directly above the surgical field, e.g. on the basis of objects or characteristics of the objects defined in advance, an alignment of the light rays can happen.

Alternatively, a region captured by the 3D sensor6not being illuminated can be used for the gesture control, whereas, within the spaces of the light rays, shadow prevention and alignment of the light rays, namely a position and a diameter of the light field, can be distinguished by a spatial allocation of the objects or typical characteristics. For example, almost circular objects having a certain size, implying a head, or objects comprising a marking—e.g. in a surgical head covering—are used for shadow prevention. On the other hand, for the alignment of the light rays, typical shapes of surgical tools or of surgical instruments are used.

InFIG. 2, a side view of the lamp body1is shown. The lamp body1has a central axis7. The illuminants3in the lamp body1radiate their light via light rays I, II, II′. Each of the illuminants3in the lamp body1emits one of the light rays I, II, II′, wherein, inFIG. 2, merely the three light rays I, II, II′ are illustrated for a clear illustration.

In order to explain the principle of the embodiment, the light rays I, II, II′ of all of the illuminants3are directed to the central axis7of the lamp body1, wherein, it is assumed in simplified terms that the intersection points PI, PIIare generated by each light ray I, II, II′ and the central axis. As exemplarily shown by the light rays I, II, II′, the light rays intersect the central axis7at different distances. Due to the simplified illustration including the three light rays, only two intersection points PI, PIIare shown here, wherein it is illustrated that merely the one light ray I is directed to the intersection point PIand two light rays I, II′ are directed to the intersection point PII. Actually, several intersection points of several light rays and the central axis7exist, wherein also several light rays (also more than two light rays as shown by means of the intersection point PII) can intersect the central axis7at the same intersection point. Actually, light rays not being directed to the central axis7can also be provided.

The light ray I generates a light field L1and the light rays II, II′ generate a light field L2on the surgical field. The light rays I, II, II′ are superimposed to generate a resulting light field having a determined light field diameter and a determined light distribution in the light field. By a distinct control of the illuminants3by the control device4, it is possible to adjust the light field diameter and the light distribution in the resulting light field.

InFIG. 2, a surface of the human body on which the surgical field is located is illustrated in a simplified manner by the horizontal line A. The human body which is regarded as the detected object in this context is at a spatial position which is detected as distance between the lamp body1and the surgical field on the surface A of the human body.

The light ray I is directed to the intersection point PIbeing located at the distance of the surgical field from the lamp body1on the central axis7. The light rays II, II′ are directed to the intersection point PIIon the central axis not being located at the distance of the surgical field from the lamp body1.

In order to focus the light rays I, II, II′ on the surgical field, the one illuminant3, the light rays I of which are directed to the intersection point PI, the distance of which is identically equal to the distance of the surgical field from the lamp body1, and which generates the light field L1is operated solely or with an increased performance with respect to the other illuminants3. If no intersection point PI, PIIat the distance of the surgical field exists, those of the illuminants3, the light rays I, II, II′ of which generate an intersection point P1. P2, the distance of which from the lamp body1is closest to the distance of the surgical field from the lamp body1, are operated. These illuminants3are either solely operated or together with other illuminants3, however, then with increased performance with respect to the other illuminants3.

Otherwise, in order to adjust a light field diameter by different controls of the illuminants3, the control device4controls the illuminants3such that the one of the illuminants3, the light ray I of which intersects the central axis7at the distance of the surgical field, as well as the ones, the light ray II, II′ does not intersection the central axis7at the distance of the surgical field, are operated with performances geared to each other. For a light field diameter as small as possible, the ones of the illuminants3are operated, the light rays I of which intersect the central axis at the distance of the surgical field, in order to generate the light field L1as described above. For an enlargement of the diameter of the light field L1, L2, the ones of the illuminants3, the light rays II, II′ of which do not intersect the central axis7at the distance of the surgical field, are operated with increased performance. By these light rays II, II′, the light field L2, the diameter of which is larger than that of the light field L1, is generated. In order to generate a light field diameter which is larger than that of the light field L1but smaller than the diameter of the light field L2, the illuminants3generating the light field L1and the illuminants3generating the light field L2are respectively operated with a performance geared to each other. Thereby, when simultaneously operating the illuminants3generating the light field L1and the illuminants3generating the light field L2, a light field, the resulting light field diameter of which is between the diameters of the light field L1and of the light field L2, resulting thereof can be generated. The larger the proportion of the emitted intensity of the illuminants3generating the determined light field diameters L1and L2of an overall performance is, the closer is the resulting light field diameter to this determined light field diameter. When the illuminants3are operated with a performance geared to each other, on the one hand, the resulting light field diameter is adjustable and, on the other hand, the illumination, i.e. the brightness, in the surgical field is adjustable.

By measuring the distance of the lamp body1from the surgical field, it is also optionally possible to control the illuminants3such that the illumination in the center of the surgical field remains constant upon a change of the distance. The associated power values are thereby either empirically detected and stored in the memory area of the control device4or calculated via an algorithm.

In a further option, a topography of the surgical field is detected. From the characteristics of the surgical field, as e.g. the size, the depth, or the inclination, the control device4determines which illuminants3are operated in order to illuminate the surgical field in a possibly optimal manner. Upon large-area surgical fields, e.g. the ones of the illuminants3generating a light field L1, L2having a large diameter are operated. In the case of small surgical fields, the ones of the illuminants3generating a light field L1, L2having a small diameter are operated. The diameter of the light field L1, L2basically corresponds to the size of the surgical field. In the case of deep surgical fields, the ones of the illuminants3, the light ray I, II, II′ of which is directed possibly vertically to the surgical field are operated in order to illuminate the entire depth of the surgical field.

In a further alternative embodiment, the surgical lamp is used in a system of at least two surgical lamps.

Although each of the surgical lamps on its own complies with the admissible ranges for the illuminance in the surgical field, in a case in which the light rays are directed to the same surgical field, there is the risk that the maximum admissible illuminance is exceeded by a superposition of the light fields of several surgical lamps. Thereby, there is the risk of glare of the surgical personnel and of desiccation of the wound in the surgical field.

In order to avoid this, the spatial arrangement of the surgical field is respectively recognized by the 3D sensors6of the individual surgical lamps. By the respective control devices4of the surgical lamps, it is determined whether the light rays I, II, II′ of the illuminants3are directed to the same surgical field and generate a light field L1, L2thereon. If it is determined by the control devices4that the light rays I, II, II′ are directed to the same surgical field, the performance of the illuminants3directed to the surgical field is tuned such that the maximum admissible illuminance, or optionally a settable maximum illuminance, is not exceeded.

Optionally, there is also the possibility to detect the actual illuminance in the surgical field by another kind of sensor, e.g. a brightness sensor, or to detect a temperature in the surgical field by a temperature sensor in order to avoid desiccation of the wound.

Furthermore, in the case in which several surgical lamps are directed to the same surgical field, there is the possibility to achieve shadow prevention not only by the control of the illuminants3of the lamp body1, the 3D sensor of which detects the object. When detecting the object between the lamp body1and the surgical field, on the one hand, additionally to a dimming or switching off of the illuminants3, the object being located in the light ray I, II, II′ thereof, the other illuminants3of the same lamp body1are operated with an increased performance by the control device4. Furthermore, the control devices4of the other surgical lamps being also directed to the same light field L1, L2, attuned with the control device4of the surgical lamp, the 3D sensor of which detects the object, control their illuminants3with an increased performance if no object is located in their respective light rays I, II, II′.

Optionally, the control device4of the individual surgical lamps control the illuminants3attuned with each other such that the illumination in the surgical filed remains at least almost constant.

In operation, a spatial position of at least one of the objects, one of the body parts of the surgical personnel or one of the surgical apparatuses, is detected by the 3D sensor6. The corresponding data concerning the spatial position of the object are transmitted to the control device4. Subsequently, the illuminants3are controlled according to the spatial position detected by the 3D sensor.

Optionally, also the size of the object being located between the lamp body1and the surgical field is detected. The ones of the illuminants3, the light ray I, II, II′ of which is directed to the object, are then the dimmed or switched off in order to prevent shadowing by the object. In order to compensate the reduced brightness in the surgical field caused by the switching off or the dimming, the ones of the illuminants3, the light rays I, II, II′ of which are directed past the object to the surgical field, are operated with an increased performance so that the brightness in the surgical field remains almost constant.

If, additionally to the spatial position, a motion or a contour of the object is detected, it can predicted which position will be occupied by the object at a certain point of time. Thus, e.g. from a velocity or an acceleration in a certain direction, this predetermined position at a certain point of time can be calculated. The illuminants3are then controlled by the control device4such that the illuminants3, the respective light ray of which is directed to the predetermined position at this point of time, is not operated or only in a dimmed manner. The light rays which then are not directed to the predetermined position of the object and then are directed past the object to the surgical field are operated with increased performance as elucidated above.

The motion of the detected object is optionally not only used for shadow prevention, however, also for controlling the surgical lamp. Thus, e.g. a motion of a hand, i.e. a gesture of a surgeon, detected by the same 3D sensor6is used for executing a certain control of the illuminants3by the control device4, e.g. a switching off or dimming, according to its direction, its trajectory, its velocity or its acceleration.

In order to focus the light rays directed to the surgical field, only or mainly the ones of the illuminants3which are directed to the intersection point where the light ray I of which intersects the central axis7, or to a point which is closest to the distance of the surgical field are operated.

In order to adjust the light field diameter to a requested size, the illuminants3being directed to a point on the central axis7at the distance of the surgical field and also the illuminants3not being directed to the point on the central axis7at the distance of the surgical field are operated with the attuned performance as described above.

In order to facilitate the operation of the surgical lamp, the illuminants3are controlled by the control device4such that upon a change of the distance between the lamp body1and the surgical field, the illuminance in the center of the light field L1, L2remains constant.

In order to illuminate the surgical field as optimally as possible, the topography of the surgical field is detected by the 3D sensor6. From the characteristics of the surgical field, such as the size, the depth or the inclination, the control device4determines the illuminants3to be operated in order to illuminate the surgical field as described above.

The various embodiments can be combined to one another.