WO2011153599A1

WO2011153599A1 - Hospital equipment for use in phototherapy

Info

Publication number: WO2011153599A1
Application number: PCT/BR2011/000155
Authority: WO
Inventors: Djalma Luiz Rodrigues; Fahim Gouveia
Original assignee: Djalma Luiz Rodrigues; Fahim Gouveia
Priority date: 2010-06-08
Filing date: 2011-05-24
Publication date: 2011-12-15
Also published as: BRPI1002129A2

Abstract

The present invention relates to a hospital equipment for use in phototherapy comprising at least a bed (1) for accommodating at least one patient (P). In addition, the hospital equipment also comprises a light source (2), directed to bed (1), capable to emit a suitable irradiance for phototherapy. The hospital equipment further comprises at least ae diffuser (3) positioned between the light source (2) and the bed (1), wherein the diffuser (3) is a holographic diffuser. The present invention also relates to a hospital equipment for phototherapy comprising, in addition to the bed (1) and light source (2) cited above, at least a photodetector (4), positioned under the bed (1), capable to measure the amount of irradiance emitted by the light source (2) that reaches the bed (1). In addition, the hospital equipment comprises at least an actuator (5), operably associated with the light source (2), capable to increase or reduce the magnitude of electric current provided to the light source (2). The hospital equipment also comprises at least a control unit (6) operably associated with the photodetector (4) and with the actuator (5), configured to control the actuator (5) based on at least one datum provided by the photodetector (4).

Description

"HOSPITAL EQUIPMENT FOR USE IN PHOTOTHERAPY".

The present invention relates to a hospital equipment for use in phototherapy, which provides an uniform and homogeneous distribution of irradiance over the body of a patient.

The present invention also relates to a hospital equipment for use in phototherapy, which allows specific adjustments of irradiance in different areas of the patient's bed in a controlled and automated manner, without requiring manual intervention by an operator.

Description of the Prior Art

Hyperbilirubinemia consists of an anomaly, usually observed in newborns (neonates), related to an increase in serum bilirubin levels in the organism, which can cause a yellowish color in the sclera, mucosa and/or skin, called jaundice. Neonatal jaundice affects approximately 60% of newborns, of which 10 to 15% require treatment.

The treatment of hyperbilirubinemia began in England in the late

1950s when it was observed that the exposition of the skin on a jaundiced neonate to sunlight significantly reduced serum bilirubin levels. In view of the above, the first phototherapy devices were designed with fluorescent bulbs that operate in the visible light spectrum in the blue band (wavelength of light between 400 and 550 nm), which are used today. These phototherapy devices are capable to transform bilirubin molecules into nontoxic isomers, which are water soluble, to be eliminated from the organism through the kidneys.

With the advancement in technology over time, other types of light sources have been developed which present higher efficiency, such as fluorescent bulbs capable to emit blue light, halogen lamps, LED lamps, and now the Super-LEDs, which are used, for example, in phototherapy equipment Bilitron^® 3006 produced by Fanem^® Inc.

The Super-LEDs are more economical, efficient and consume less energy compared to conventional LEDs due to its preferential composi- tion of indium gallium nitride (conventional LEDs comprise only gallium nitride).

Although the high efficiency and reliability of LEDs, one of its de- ficiencies when used in phototherapy is that they do not provide uniformity and homogeneity of radiation on the surface of the patient's bed, since they consist of point light sources. It should be noted that a uniform and homogeneous distribution of irradiance over the surface where phototherapy takes place represents a significant improvement in phototherapy effectiveness.

Particularly, LEDs used in phototherapy can be classified in two categories according to the optical power level generated: the conventional low-power LEDs (less than 50 mW of radiation within the range from 400 to 550 nm); and high-brightness LEDs (greater than 500 mW of radiation within the range from 400 to 550 nm).

Regarding the conventional LEDs, which have low optical power, they are usually set up in a continuous queue format, with no spaces between them, in order to increase the intensity of radiation over the surface of the patient's bed. Consequently, it becomes necessary to implement hun- dreds of conventional LEDs for generating acceptable radiation on the surface of treatment. It should be noted that, due to the difference in light intensity (visible irradiance power emitted by a light source available in a certain direction) that normally exists between LEDs, it is observed that there is not an ideal uniformity and homogeneity of the distribution of irradiance on the surface of treatment. Therefore, each part of the patient's body can receive a different dose of irradiance (greater or less than ideal), especially when the patient is not in an ideal position in bed, which could jeopardize the effectiveness of phototherapy.

On the other hand, the use of high-brightness LEDs, which have high radiation, enables considerable reduction of the number of LEDs used from the order of units to tens of units. Therefore, the high-brightness LEDs can be positioned at greater distances from each other when compared with conventional LEDs. However, similarly to conventional LEDs, irradiance distribution over the surface of treatment is not uniform or homogeneous, as previously explained.

In addition, for phototherapy to be performed in an effective manner, it is recommended to constantly control and monitor the intensity and distribution of the light to be applied to the patient's body.

Normally, such monitoring of light intensity is performed manually by an operator using a device capable to capturing light energy emitted by a light source, for example, a dedicated radiometer that measures irradiance (amount of light or energy emitted per unit of area in a given range of the spectrum). More specifically, the radiometer is capable to provide irradiance values in a given range of the spectrum of a light source. In phototherapic applications, the radiometer should be configured to measure irradiance in the visible blue spectrum, what is normally used in phototherapy for the treatment of hyperbilirubinemia in order to be more effective transforming bilirubin molecules into isomers.

Thus, from measurements performed by the radiometer, the operator (physician, nurse or technician) adjusts (increases or decreases) the intensity of the light source of the phototherapy equipment as needed. In oth- er words, the control of the light source intensity of the phototherapy equipment is also performed manually by the operator.

Therefore, both monitoring the irradiance and controlling the intensity of the light source are normally performed manually, making it difficult to obtain a stable and precise adjustment of the irradiance received by the patient, apart from the increased susceptibility to human errors (for example: wrong or delayed decision made by the operator); in addition, it is necessary to have an operator exclusively to perform these tasks. Therefore, it is also important to note that if the light sources emit a greater amount of irradiance than the necessary, the life cycle of the equipment is reduced. On the other hand, if the sources of light emit less irradiance than necessary, phototherapy efficacy/performance may be compromised (which is aggravated when the patient is not in an ideal position in bed for treatment).

In view of the above, in order to provide automated monitoring of irradiance and control of the light source intensity, the European patent doc- ument EP 0 616 820 disclosed a servo-controlled system for application in neonatal phototherapy. In general lines, said document describes an equipment that comprises a light source, a bed, a light detector and a regulator capable to automatically adjust the light source intensity provided to the bed based on the measurements made by the light detector.

However, the equipment described in said European patent (EP 0 616 820) does not allow specific adjustments of irradiance in different areas or regions of the patient's bed surface, which reduces its efficacy/performance, limiting the field of application. In addition, it is difficult to obtain a uniform and homogenous distribution of irradiance throughout the surface of the bed, mainly in peripheral parts (edges and ends). Moreover, said equipment does not allow compensation for any undesirable decrease of irradiance in some areas of said bed. It is also important to observe that the equipment requires the use of optic fibers for transmitting light from the source to the patient and also from the area of the bed that is in contact with the patient to the light detector (photodetector), since the light source is not directed towards the patient, increasing production costs.

Therefore, there is a gap in the prior art that the present invention aims at filling, as can be seen later in this specification.

Objects of the Invention

The first object of the present invention is to provide a hospital equipment for use in phototherapy, which enables uniform and homogeneous distribution of irradiance on the extent of a patient's body, regardless of their position in bed, so as to provide an optimum condition of the body surface covered by irradiance.

The second object of the present invention is to provide a hospital equipment for use in phototherapy, capable to automatically maintain the irradiance received by the patient stable and accurate, in order to prevent inadequate doses of irradiance to be applied on the patient, without the needing of manual interference by an operator, which optimizes the effectiveness of treatment and also prolongs the life cycle of the devices used.

Furthermore, the third object of the present invention is to pro- vide a hospital equipment for use in phototherapy, which allows automatic monitoring and control of the distribution of irradiance received by a patient without the needing of manual interference by an operator, eliminating the inconvenience of using an autonomous radiometer (stand-alone).

Finally, the fourth object of the present invention is to provide a hospital equipment for use in phototherapy, capable to provide specific adjustments of irradiance in different areas of the patient's bed in a controlled and automated manner, which enables a more effective treatment, and to provide compensation for any undesirable decrease of irradiance in some parts of the bed.

Brief Description of the Invention

The first object of the present invention is achieved by a hospital equipment for use in phototherapy comprising at least a bed for accommodating at least one patient. In addition, the hospital equipment also comprises at least one light source, directed to the bed, capable to emit a suitable irradiance for phototherapy. Additionally, the hospital equipment further comprises at least one diffuser positioned between the light source and the bed, wherein the diffuser is a holographic diffuser.

The first, second, third and/or fourth object(s) of the present invention is (are) also achieved by a hospital equipment for use in phototherapy comprising at least:

- a bed for accommodating at least one patient;

- a light source directed to the bed, wherein the light source is capable to emit a suitable irradiance for phototherapy;

- a holographic-type diffuser positioned between the light source and the bed.

In addition, the objects of the present invention are achieved by a hospital equipment for use in phototherapy comprising at least:

- a bed for accommodating at least one patient;

- a light source directed to the bed, the light source being capable to emit a suitable irradiance for phototherapy;

- one or more photodetectors positioned under the bed, wherein the photodetector is capable to measure the amount of irradiance emitted by the light source that reaches the bed;

- an actuator operably associated with the light source, wherein the actuator is capable to increase or reduce the magnitude of electric current provided to the light source; and

- a control unit operably associated with the photodetector and with the actuator, wherein the control unit is configured to control the actuator based on at least one datum provided by the photodetector.

In addition, the objects of the present invention are achieved by means of a hospital equipment for use in phototherapy comprising at least:

- a bed for accommodating at least one patient;

- a light source directed to the bed, the light source being capa- ble to emit a suitable irradiance for phototherapy;

- a holographic-type diffuser positioned between the light source and the bed.

- one or more photodetectors positioned under the bed, wherein the photodetector is capable to measure the amount of irradiance emitted by the light source that reaches the bed after control of the emission angles of light by the diffuser;

Brief Description of the Drawings

The present invention will be described in more detail below, with reference to the attached drawings, wherein:

Figure 1 - illustrates a representative diagram of a hospital equipment, for application in direct phototherapy, which is the object of the present invention.

Figure 2 - illustrates a representative diagram of a hospital equipment, for application in reverse phototherapy, which is the object of the present invention.

Figure 3 - illustrates a representative diagram of a hospital equipment, for application in phototherapy, which is the object of the present invention, capable to automatically control irradiance from the light source.

Figure 4 - illustrates a control closed-loop system of the hospital equipment represented in Figure 3;

Figure 5 - illustrates a first embodiment for placement of a pho- todetector under the bed of the hospital equipment represented in figure 3;

Figure 6 - illustrates a second embodiment for placement of pho- todetectors under the bed of the hospital equipment represented in figure 3; and

Figure 7 - illustrates a third embodiment for placement of photo- detectors under the bed of the hospital equipment represented in figure 3.

Detailed Description of the Drawings and the Invention

Figure 1 illustrates a representative diagram of a hospital equip- ment, for application in phototherapeutic treatments, according to a first preferred embodiment of the present invention.

Said hospital equipment, the subject matter of the present invention, comprises at least one bed (1) for accommodating at least one patient (P). Preferably, the bed (1) is transparent, so as to allow the light to pass through it with a regular and well defined path. Optionally, the bed (1) may be translucent. In both cases, the bed (1) can be used both for direct phototherapy (figure 1) and for reverse phototherapy (figure 2), so as to benefit the usability of the hospital equipment, since its scope of applications is increased.

As it can be seen in figures 1 and 2, the hospital equipment also comprises at least one light source (2), capable to emit a suitable irradiance for phototherapeutic treatments, directed to the bed (1 ). Preferably, in the treatment of bilirubinemia by phototherapy, a visible light is applied on the patient through light source (2). It should be noted that, differently from some types of phototherapy devices currently known, the light source (2) is directed toward the bed (1), thus not needing to use optical fibers to transmit the light, so as to optimize the efficiency in the phototherapeutic treatment and also reducing production costs.

The light source (2) comprises a plurality of LEDs and/or Super- LEDs (9) which emit light in the blue range of the light spectrum, wherein each LED or Super-LED (9) is associated with a collimator lens capable to guide the light emitted by LED or Super-LED (9) to a predefined direction. As already previously described, the LEDs are provided with gallium nitride (GaN) and the Super-LEDs are provided with indium gallium nitride (InGaN). Preferably, the LEDs or Super-LEDs (9) are distributed so as to encompass or cover the whole surface of bed (1) in a uniform manner.

Alternatively, the light source (2) can comprise at least one fluorescent lamp, at least one halogenous lamp, or even any light emission means whose irradiance is suitable for the treatment of hyperbilirubinemia, since the equipment configuration is adaptable and flexible to any type of light emission means.

The hospital equipment also comprises at least one diffuser (3) positioned between the light source (2) and the bed (1). Preferably, the diffuser (3) consists of a holographic diffuser film, overlaid to the LED or Super- LED (9), having a light transmittance above 85%.

More particularly, diffuser (3) is a film or a plate whose surface is composed by microstructures generated by holographic techniques, wherein each microstructure acts similarly to a microlens. Said diffuser microstructures are generated over the diffuser film from a holographically imprinted matrix. The diffusers (3) overlaid on the LEDs or Super-LEDs (9) can be used in other applications, such as in LEDs surgical lamps, as well as in other medical applications which require a broadening of the light area with homogeneity of emitted light, such as for instance, in the esthetics field (for instance: treatment of vitiligo) or the odontology field (for instance: in the ho- mogenization of the light point in the resin polymerization area).

It should be noted that the holographic diffusion does not depend on the wavelength, acting effectively in the range of 200 to 1600 nm. Additionally, the incident light is precisely controlled in the border of well-defined areas, since it does not escape from said limits, resulting in a higher photon surface density. Thus, the diffuser (3) enables the control of the light emission angles.

As a result of the aforementioned characteristics, the holographic diffuser film or plate has a good transmittance (between 85% and 92%), while the conventional diffuser plates (or collimators) made of plastic (for instance, acrylic) or even glass do not have the same light transmission efficiency (transmittance lower than 70%).

In sum, the diffuser (3) can be applied in phototherapies by a direct or reverse LEDs or Super-LEDs (9) source. In the direct phototherapy the radiation source is positioned above the patient, and the diffuser (3) is coupled to the light source (2), as illustrated in figure 1. In the reverse phototherapy, wherein the light source (2) is positioned below the bed (1) on which is patient P, the diffuser (3) is positioned between the bed (1) and the light source (2), as illustrated in figure 2.

As seen in figures 3 and 4, in a second preferred embodiment of the present invention, which may or may not have the abovementioned dif- fusers (3), the hospital equipment also comprises at least one photodetector (4), positioned under the bed (1) and capable to measure the amount of irra- diance emitted by the light source (2) that reaches the bed (1). Thus, the photodetector (4) is capable to detect the irradiance that reaches the bed (1), that is, it is configured to measure irradiance in the visible blue spectrum (400 to 550 nm), used in phototherapy for the treatment of hyperbilirubinemia in newborn patients. It should be noted that the photodetector (4) may be of the photovoltaic or of the photoconductive type.

Therefore, the hospital equipment of the present invention incorporates the function of a radiometer or a photometer that measures and processes the irradiance values. More specifically, the radiometer or photometer per se consists of an apparatus capable to measure the amount of light or potency emitted by area unit in a certain spectrum, that is, measure irradiance in a certain range of the light spectrum emitted by a known light source (2).

The photodetector (4) is provided with an optical sensor capable to convert the intensity of light reaching an electrical signal, such as for instance, an electric current or voltage. In other words, the optical sensor provides an electrical signal according to the variation of light reaching it. The optical sensor is operatively associated to a conditioning electronic circuit, so that the physical magnitude can be converted to an analogical electrical signal in order to be further amplified and/or converted to a digital electrical signal. Naturally, said sensor can be provided in the form of a transducer. As a possible example of an optical sensor, it can be cited a silicon photodiode that, when operated in a photoconductive mode, provides a linear electric current according to the variation of light reaching it, tough any other similar device can be used.

Additionally, the photodetector (4) has a light diffuser, operatively associated to the optical sensor, capable to correct the effect of the inclination of the light beams emitted by the light source (2) of the optical sensor.

Furthermore, optionally, the photodetector (4) comprises a light filter placed between the light diffuser and the optical sensor, syntonized to capture light waves having wavelengths varying between 400 to 550 nm. This range of wavelength values defines a blue light spectrum, suitable for the treatment of hyperbilirubinemia, that is, in said spectrum there is optimum light absorption by bilirubin. The light filter may consist of an optical filter by absorption or interference or even a combination of them.

Therefore, as a general rule, the photodetector (4) is configured to capture light waves having wavelengths varying between 400 to 550 nm.

In this second preferred embodiment, other types of diffusers, such as for instance, acrylic or polycarbonate diffusers (collimators), can also be used. As previously described, the diffuser (3) aids in the uniformization of irradiance, allowing the irradiance to reachthe bed (1) to be substantially homogeneous on the entire treatment surface and, consequently, on the patient's body.

Also according to figure 4, the hospital equipment also comprises at least one actuator (5), operably associated with the light source (2), capable to increase or reduce the magnitude of electric current provided to the light source (2). The actuator (5) consists of an electric circuit capable to carry out actuation techniques by continuous current variation or by a pulse width modulation (PWM) technique.

The hospital equipment also comprises at least one control unit (6) operably associated with the photodetector (4) and with the actuator (5), configured to control the actuator (5) based on at least one datum provided by the photodetector (4).

More specifically, the control unit (6) is configured to compare at least one datum provided by the photodetector (4), corresponding to a mea- surement of the irradiance reaching the bed (1), with an irradiance value corresponding to a desired operation condition.

Said desired operation condition can be pre-established or determined manually by an operator through at least one adjustment means (7) comprised by the hospital equipment. Thus, said adjustment means (7), operably associated with the unit control (6), is capable to adjust the irradiance amount emitted by the light source (2) to the irradiance value corresponding to the desired operation condition. The adjustment means (7) consists of a key, an electronic key or any other suitable means (mechanic, electric, or electric-mechanic) that enables the selection of variables, such as for instance, a touch screen.

The control unit (6) is also configured to increase or reduce the irradiance emitted by the light source (2) automatically sending a command signal to the actuator (5). This automatic increase or reduction is needed in order to the equipment to work in the desired irradiance condition (manually pre-established or determined). Therefore, the phototherapy equipment of the present invention is capable to maintain the desired irradiance level throughout the entire phototherapeutic treatment, for the automatic control (servo-control) to correct eventual deviations of the irradiance level resulting from an eventual increase in temperature or wear in the components and the sources, etc., without the need of manual intervention by an operator/user. Additionally, this avoids that the light sources (2) emit more radiation than necessary, thus increasing their life cycle. Preferably, the control unit (6) consists of a programmable microprocessor or microcontroller. Alternatively, the control unit (6) can be replaced with an equivalent electronic circuit having analogical and/or digital electronic components, with no loss to the invention. Therefore, theautomatic control of irradiance emitted by the light source (2) is preferably done by means of a computer algorithm to be executed by the microprocessor or microcontroller.

Figure 5 illustrates a first embodiment for placement of a photo- detector (4) the bed (1) of the hospital equipment, wherein the photodetector (4) is placed beneath the center of the bed (1).

Preferably, the hospital equipment comprises a plurality of pho- todetectors (4) wherein each photodetector (4) is arranged in a specific predefined position under the bed (1).

For instance, the photodetectors (4) can be positioned in the ends (edges) of the bed (1). In this case, the homogenization of irradiance in the edges of the bed (1) can be improved with the use of LEDs/photodetector pairs properly arranged in corresponding position of the bed (1) and of the light source (2), which would have a specific adjustment to compensate the decrease of irradiance in the edges.

Another example of arrangement of the photodetectors (4) can be seen in figure 6, which illustrates a second embodiment for placement of the photodetectors (4) under the bed (1) of the hospital equipment. In this second embodiment, the hospital equipment comprises three sets consisting one or more LEDs or Super-LEDs (9) arranged under a longitudinal axis of the bed (1), being each set associated with an actuator (5) independent from the others. Therefore, said embodiment allows identifying an eventual difference of irradiance reaching the different positions of the longitudinal axis of the bed (1) and correct it as desired.

Figure 7 illustrates a third embodiment for placement of the pho- todetectors (4) under the bed (1) of the hospital equipment. In said third embodiment, the hospital equipment comprises five sets consisting of one or more LEDs or Super-LEDs (9), being one of them positioned under the cen- ter of the bed and each of the remaining ones is positioned under the center of each quadrant of the bed (1). Each set is associated with an actuator (5) independent from the others. Said embodiment allows identifying more precisely an eventual difference of irradiance reaching the different regions (qu- adrants) of the bed (1), and correcting it as desired. Additionally, in said embodiment it is possible to control the LEDs or Super-LEDs (9) positioned under the ends (edges) of the bed (1) so that they emit enough irradiance to reduce the difference in relation to the irradiance emitted by the LEDs or Super-LEDs (9) positioned under the central region of the bed.

It should be noted that, as seen in figures 5 to 7, the bed (1) has a substantially rectangular shape comprising four substantially rectangular portions configured in the form of quadrants and arranged adjacently to each other.

In sum, more than one photodetector (4) can be used in the hos- pital equipment of the present invention, in case one wants to control the irradiance in different regions of the bed (1), so as to obtain better uniformity and homogeneity. For instance, the irradiance of the corresponding LEDs or Super-LEDs (9) can reach the peripheral areas of the bed (1) when adjusted to higher values in relation to the irradiance of the LEDs or Super-LEDs (9) that cover the central region of the bed (1), in order to compensate the difference of irradiance between said regions.

Naturally, the amount and the positioning configuration of the photodetectors (4) are not limited to the examples given herein, and may vary according to the application and the need, which represents a great flex- ibility in the use of the hospital equipment.

Whatever the positioning configuration, each photodetector (4) is operably associated with the control unit (6) which, in turn, processes the reading datum (measurement) of each photodetector (4), in order to increase or reduce the irradiance of the corresponding LED(s) or Super-LED(s) (9), that is, of the LED(s) or Super-LED(s) (9) closest to their respective photodetector (4). Therefore, each photodetector (4) receives irradiance from one or more sets of corresponding LEDs or Super-LEDs (9). In other words, the control unit (6) is configured to increase or reduce the irradiance of each set of LEDs or Super-LEDs (9) separately and independently from the other sets of LEDs or Super-LEDs (9) comprised by the phototherapy equipment, based on the data provided by their respective photodetectors (4). The LEDs or Super-LEDs (9) of light source (2) can be grouped into different electronic circuits, according to its position in relation to the photodetectors (4), so that each LED or Super-LED (9) can have its irradiance controlled independently from the other LEDs or Super-LEDs (9), enabling the obtainment of a more uniform and homogeneous radiation dis- tribution.

Preferably, the control unit (6) is configured to identify wear in the light source (2) based on the signal levels applied to the actuators (5) necessary to maintain the desired irradiance. More specifically, the control unit (6) identifies an eventual decrease that may occur in the efficiency of light source (2), for instance, due to the natural wear of the LEDs or Super-LEDs (9) comprised by light source (2). In case of this decrease occurs, control unit (6) processes said information to alert the operator/user about a possible need to change said LEDs or Super-LEDs (9) which may have reached the end of their life cycle. In other words, the nearness of the end of the LEDs or Super-LEDs (9) life cycle is easily identifiable by the hospital equipment, for their wear is assessed by the control unit (6) as a higher electric current is needed to maintain the desired irradiance level.

Said alert can be made through a monitor (8) comprised by the hospital equipment. Said monitor (8) (for instance: a LCD screen), operably associated with the control unit (6), is capable to allow visualization or hearing of at least one irradiance value measured by the photodetector (4). It should be noted that the preferred irradiance unit shown by the monitor (8) is uW/cm².nm (micro Watts per square centimeter per nanometer). Naturally, monitor (8) can be configured to exhibit different data and information about the functioning and operation of the hospital equipment, working as an interface means between the operator/user and the equipment.

The hospital equipment also comprises at least one interface unit (not illustrated), operably associated with the control unit (6), configured to enable communication between the system with an external device, such as for instance, a PC microcomputer which can receive data relating to the patients' charts or technical data about the functioning/operation/components of the hospital equipment. The interface unit can consist of a RS 232, USB, wireless (wi-fi, bluetooth, zigbee, etc.), Firewire interface or any known communication means. This type of communication enables the monitoring, evaluation and analysis of data collected/calculated/measured by the system, in order to ease the checking of the phototherapeutic treatment, the carrying out of preventive/corrective maintenance and/or the verification of the phototherapy equipment efficiency. For instance, to verify the efficiency in phototherapy equipments, it is recommended that Brazilian technical norm NBR IEC 60601-2-50:2003, which establishes in its sub-clause 50.104 the measurement of the total irradiance for bilirubin, be followed.

After examples of preferred embodiments have been described, it should be understood that the scope of the present invention encompasses other possible embodiments and is limited only by the content of the appended claims, which include their possible equivalents.

Claims

1. A hospital equipment for use in phototherapy comprising at least:

- a bed (1) for accommodating at least one patient (P); - a light source (2), directed to the bed (1), wherein the light source (2) is capable to emit a suitable irradiance for phototherapy; and

- a diffuser (3) positioned between the light source (2) and the bed (1),

wherein the equipment is characterized in that the diffuser (3) is a holograph- ic diffuser.

2. A hospital equipment according to claim 1 , characterized in that the diffuser (3) consists of a holographic diffuser film having a light transmittance above 85%.

3. A hospital equipment according to claims 1 or 2, characterized in that the light source (2) comprises a plurality of LEDs and/or Super-LEDs

(9), wherein each LED or Super-LED (9) is associated with a collimator lens capable to guide the light emitted by LED or Super-LED (9) to a predefined direction.

4. A hospital equipment for use in phototherapy comprising at least:

- a bed (1 ) for accommodating at least one patient;

- a light source (2), directed to the bed (1 ), wherein the light source (2) is capable to emit a suitable irradiance for phototherapy;

wherein the equipment is characterized by further comprising at least:

- a photodetector (4), positioned under the bed (1), wherein the photodetector (4) is capable to measure the amount of irradiance emitted by the light source (2) that reaches the bed (1);

- an actuator (5) operably associated with the light source (2), wherein the actuator (5) is capable to increase or reduce the magnitude of electric current provided to the light source (2); and

- a control unit (6) operably associated with the photodetector (4) and with the actuator (5), wherein the control unit (6) is configured to control the actuator (5) based on at least one datum provided by the photodetector (4).

5. A hospital equipment according to claim 4, characterized in that the control unit (6) is configured to compare the datum provided by the photodetector (4) with an irradiance value corresponding to a desired operation condition, wherein the control unit (6) is also configured to increase or reduce the irradiance emitted by the light source (2) by sending a command signal to the actuator (5).

6. A hospital equipment according to claim 5, characterized in that it comprises at least an adjustment means (7) operably associated with the control unit (6), wherein the adjustment means (7) is capable to adjust the irradiance amount emitted by the light source (2) to the irradiance value corresponding to the desired operation condition.

7. A hospital equipment according to any one of claims 4 to 6, characterized in that it comprises at least a diffuser (3) positioned between the light source (2) and the photodetector (4).

8. A hospital equipment according to claims 4 to 7, characterized in that the light source (2) comprises a plurality of LEDs and/or Super-LEDs (9), wherein each LED or Super-LED (9) is operably associated with a colli- mator lens capable to guide the light emitted by LED or Super-LED (9) to a predefined direction.

9. A hospital equipment according to any one of claims 4 to 8, characterized in that it comprises a plurality of photodetectors (4) wherein each photodetector (4) is arranged in a specific predefined position under the bed (1).

10. A hospital equipment according to claim 9, characterized in that the control unit (6) is configured to increase or reduce irradiance of each set of LED or Super-LED (9) separately and independently from the other sets of LEDs or Super-LEDs (9) comprised by the phototherapy equipment, based on the data provided by the respective photodetectors (4).

11. A hospital equipment according to any one of claims 4 to 10, characterized in that the bed (1) has a substantially rectangular shape com- prising four substantially rectangular portions configured in form of quadrants and arranged adjacent to each other.

12. A hospital equipment according to any one of claims 4 to 11 , characterized in that the control unit (6) can be configured to identify wear in the light source (2) based on the ratio between the signal levels applied to the actuators 5 and the corresponding irradiances obtained.

13. A hospital equipment according to any one of claims 4 to 12, characterized in that it comprises at least a monitor (8) operably associated with the control unit (6), wherein the monitor (8) is capable to allow visualiza- tion or hearing of at least irradiance value measured by the photodetector (4).

14. A hospital equipment for use in phototherapy comprising at least:

- a bed (1 ) for accommodating at least one patient;

wherein the equipment is characterized by further comprising at least:

- a holographic-type diffuser (3) positioned between the light source (2) and the bed (1);

- a photodetector (4), positioned under the bed (1 ), wherein the photodetector (4) is capable to measure the amount of irradiance emitted by the light source (2) that reaches the bed (1 ) after control of the emission angles of light by the diffuser (3).

- a control unit (6) operably associated with the photodetector (4) and with the actuator (5), wherein the control unit (6) is configured to control the actuator (5) based on at least one datum provided by photodetector (4).