CN211293575U

CN211293575U - Projection device

Info

Publication number: CN211293575U
Application number: CN202020102644.2U
Authority: CN
Inventors: 蔡德颖; 詹昆洁
Original assignee: Coretronic Corp
Current assignee: Coretronic Corp
Priority date: 2020-01-17
Filing date: 2020-01-17
Publication date: 2020-08-18
Anticipated expiration: 2030-01-17

Abstract

The utility model provides a projection device. The projection device is provided with a closed accommodating space and comprises a heating element, a refrigerating element and an active dehumidifying unit, wherein the heating element, the refrigerating element and the active dehumidifying unit are positioned in the closed accommodating space, and the cold end surface of the refrigerating element is used for radiating heat of the heating element. The heat dissipation control method comprises the following steps. The specification temperature information obtaining unit obtains the specification temperature information, and determines the specification temperature of the refrigeration element according to the specification temperature information. The temperature and humidity sensing unit senses the ambient temperature and the ambient humidity in the closed accommodating space, and the dew point temperature is calculated according to the ambient temperature and the ambient humidity. And acquiring the cold end temperature of the cold end surface by the temperature sensing unit. And judging whether to open or close the active dehumidification unit according to the dew point temperature, the specification temperature and the cold end temperature. Therefore, the projection device of the utility model can avoid the condensation phenomenon of the refrigeration element.

Description

Projection device

Technical Field

The present invention relates to a projection apparatus, and more particularly to a projection apparatus.

Background

With the development of projection technology, projectors have been widely used in homes, offices, schools, and the like. As the brightness of projectors increases, the amount of heat that is experienced by the light valve elements or other optical elements within the projector increases. In addition, the design of the projector is proceeding toward light weight and weight reduction, and the conventional passive heat dissipation elements (such as heat dissipation fins) with a heat dissipation fan can achieve the purpose of heat dissipation, but the heat dissipation efficiency needs to be further improved.

In order to improve the heat dissipation efficiency, a Thermoelectric Cooler (TEC) may be applied to the heat dissipation system of the projector. Thermoelectric cooling devices are active heat dissipation elements based on semiconductor materials. By applying a dc voltage to the thermoelectric cooling device, heat flows from one end of the thermoelectric cooling device to the other end, thereby forming a hot side and a cold side. Therefore, the cold end of the thermoelectric refrigerating device is directly or indirectly contacted with the heating element in the projector, the thermoelectric refrigerating device can take away the heat of the heating element to achieve the purpose of heat dissipation, and the cold end of the thermoelectric refrigerating device can be cooled to be lower than the ambient temperature.

When the thermoelectric cooling device is used for radiating heat of the optical element, the condensation phenomenon is generated at the cold end of the thermoelectric cooling device. The condensation phenomenon may reduce the heat dissipation capability of the thermoelectric cooling device and may also cause damage to electronic components. The use of sealants, waterproof paints and special waterproof structures, while being moisture impervious, may result in a reduction in the cooling capacity of the thermoelectric cooling device and, at the same time, cause processing difficulties and additional costs.

The background section is only provided to aid in understanding the present invention, and therefore the disclosure in the background section may include some known techniques which do not constitute a part of the knowledge of those skilled in the art. The disclosure in the "background" section does not represent that content or the problems which may be solved by one or more embodiments of the present invention are known or appreciated by those skilled in the art prior to the filing of the present application.

SUMMERY OF THE UTILITY MODEL

The utility model provides a projection device, it can economize on electricity and avoid the refrigeration component to take place the dewfall phenomenon.

Other objects and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

In order to achieve one or a part of or all of the above or other objects, an embodiment of the present invention provides a projection apparatus. The projection device has a closed accommodating space and comprises a heating element, a cooling element, an active dehumidification unit, a specification temperature information acquisition unit, a temperature and humidity sensing unit, a temperature sensing unit and a control unit. The cooling element has a cold end surface and a hot end surface, wherein the cold end surface is used for radiating heat of the heating element. The heating element, the refrigerating element and the active dehumidifying unit are positioned in the closed accommodating space. The specification temperature information obtaining unit is used for obtaining specification temperature information. The temperature and humidity sensing unit senses the ambient temperature and the ambient humidity in the closed accommodating space. The temperature sensing unit senses a cold end temperature of the cold end surface. The control unit is coupled to the specification temperature information obtaining unit, the temperature and humidity sensing unit, the temperature sensing unit, the active dehumidification unit, the refrigeration element and the heating element, and determines the specification temperature of the refrigeration element according to the specification temperature information and calculates the dew point temperature according to the environment temperature and the environment humidity. The control unit judges whether to open or close the active dehumidification unit according to the dew point temperature, the specification temperature and the cold end temperature.

Based on the above, the embodiments of the present invention have at least one of the following advantages or effects. The utility model discloses an among the projection arrangement, borrow by initiative dehumidification unit, can judge according to dew point temperature, specification temperature and cold junction temperature whether open or close initiative dehumidification unit, or the power of adjustment refrigeration component. Thus, the condensation phenomenon of the refrigerating element can be avoided. Moreover, under the condition that the cold end temperature is lower than the specification temperature, even if the cold end temperature is also lower than the dew point temperature, the projection device can adjust and reduce the power of the refrigerating element under the condition that the active dehumidifying unit is not started, so that the effects of saving electricity and avoiding the condensation phenomenon of the refrigerating element are achieved at the same time.

In order to make the aforementioned and other features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

Fig. 1 is a schematic diagram of a projection apparatus according to an embodiment of the present invention.

Fig. 2 is a side view of a cooling element and a heat dissipation module in the projection apparatus of fig. 1.

Fig. 3 is a schematic diagram of a relationship between specification temperature and brightness according to an embodiment of the present invention.

Fig. 4 is a flowchart of a heat dissipation control method according to an embodiment of the present invention.

Fig. 5 is a schematic diagram of the relationship between the dew point temperature and the environmental condition according to an embodiment of the present invention.

Fig. 6 is a schematic view of another projection apparatus according to an embodiment of the present invention.

Detailed Description

The foregoing and other features, aspects and utilities of the present invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings. Directional terms as referred to in the following examples, for example: up, down, left, right, front or rear, etc., are simply directions with reference to the drawings. Accordingly, the directional terminology is used for purposes of illustration and is in no way limiting.

Fig. 1 is a schematic diagram of a projection apparatus 100 according to an embodiment of the present invention. Referring to fig. 1, the projection apparatus 100 of the present embodiment includes a light valve module 110, a light source 120, a brightness sensing unit 130, a cooling device 140, a temperature and humidity sensing unit 151, a temperature sensing unit 152, an active dehumidification unit 160, a control unit 170, a projection lens module 180, an optical-mechanical module 190, and a heat dissipation module 113.

In one embodiment, the light source 120 provides an illumination beam that is transmitted to the light valve module 110. The light source 120 may comprise a light emitting diode, a laser diode, or a light bulb, or other light source. The light emitted by the light source 120 is, for example, blue light, but may be other color light beams, and the disclosure is not limited thereto. For example, the light source 120 may include a plurality of laser elements (not shown) arranged in an array, for example, the laser elements are Laser Diodes (LDs), for example. In other embodiments, there may be more than one light source 120. In other embodiments, the light source 120 may be a solid-state illumination source such as a light emitting diode (light emitting diode). In yet other embodiments, the light source 120 may include a bulb (lamp).

In one embodiment, the optical-mechanical module 190 includes optical elements and directs the illumination beam generated by the light source 120 to the light valve module 110. The light valve module 110 includes, for example, a Digital Micromirror Device (DMD), which can be used to convert the illumination beam from the light source 120 into an image beam, and provide the image beam to the projection lens module 180. The projection lens module 180 is used for projecting the image beam to the outside, so that the projection apparatus 100 achieves projection. The brightness sensing unit 130 is disposed beside the transmission path of the illumination beam to sense the brightness of the illumination beam from the light source 120. More specifically, the brightness sensing unit 130 can determine the brightness of the illumination beam by sensing stray light (stray light) from the light source 120. In one embodiment, the brightness sensing unit 130 includes a photo resistor.

In one embodiment, the cooling element 140 is an active heat sink, such as a thermoelectric cooling device (TEC). The material of the thermoelectric cooling device is, for example, an N-type semiconductor, a compound of a P-type semiconductor, or other thermoelectric materials. Refrigeration element 140 has a cold end surface S1 and a hot end surface S2 (shown in fig. 2). When cooling element 140 is energized, the temperature of cold end surface S1 is lower than the temperature of hot end surface S2. Specifically, in the projection apparatus 100 of the present embodiment, the cooling element 140 can take away the heat of the optical element to dissipate the heat by the cooling surface S1 of the cooling element 140 directly or indirectly contacting the heating element in the projection apparatus 100.

In the present embodiment, the cold side surface S1 of the cooling element 140 is connected to the light valve module 110 to dissipate heat of the light valve module 110, that is, the light valve module 110 is a heating element. Specifically, cold side surface S1 of refrigeration element 140 may be thermally coupled to light valve module 110 to absorb heat from light valve module 110. A thermal conductive paste or metal (e.g., copper) may be further disposed between the cold end surface S1 of the cooling element 140 and the light valve module 110 as a thermal conductive medium, but the present invention is not limited thereto.

In one embodiment, the refrigeration component 140 can be used with the heat dissipation module 113 to dissipate heat of the light valve module 110. The hot side surface S2 of cooling element 140 may be thermally coupled to heatsink module 113 to conduct heat to heatsink module 113. In one embodiment, a thermal paste or metal (e.g., copper) may be disposed between the hot end surface S2 of the cooling element 140 and the heat dissipation module 113 as a thermal conduction medium, but the invention is not limited thereto.

Fig. 2 is a schematic side view of the refrigeration device 140 and the heat dissipation module 113 according to an embodiment of the present invention. Referring to fig. 2, the light valve module 110 is disposed on the carrier 111. One end of the metal heat conducting block 112 is connected to the light valve module 110 through the through hole of the carrier plate 111 in a heat conducting manner. The other end of metal heat conducting block 112 is connected in heat conducting manner to cold end surface S1 of cooling element 140. The hot end surface S2 of cooling element 140 is thermally conductively coupled to heat sink module 113 (e.g., a set of heat sink fins). Therefore, the cooling element 140 can conduct the heat of the light valve module 110 to the heat dissipation module 113, so as to dissipate the heat of the light valve module 110. In addition, in another embodiment not shown, the heat dissipation module 113 may also be a liquid-cooled heat dissipation system, which dissipates heat to the light valve module 110 through gas, liquid or two-phase fluid, and the invention is not limited to the heat dissipation manner of the heat dissipation module 113.

In one embodiment, the temperature and humidity sensing unit 151 is used for sensing an ambient temperature and an ambient humidity. As shown in fig. 1 and fig. 2, in the present embodiment, the projection apparatus 100 further includes an isolation layer IL and a casing H1. The isolation layer IL is used to form a closed accommodation space CA. In some embodiments, the isolation layer IL may also be used to block moisture from the outside to reduce the possibility of condensation. The light valve module 110, the cooling element 140, the temperature and humidity sensing unit 151, the temperature sensing unit 152 and the active dehumidification unit 160, which are heating elements, are located in the enclosed accommodating space CA. The cabinet H1 includes an air inlet W1, and the air inlet W1 is adjacent to the enclosed accommodating space CA. The temperature and humidity sensing unit 151 may be adjacent to one side of the air inlet W1. However, in other embodiments, the temperature and humidity sensing unit 151 may be disposed at any position where the ambient temperature and the ambient humidity can be detected, which is not limited by the present invention. For example, the temperature and humidity sensing unit 151 may be disposed adjacent to the cooling element 140.

On the other hand, in one embodiment, temperature sensing unit 152 is configured to sense the cold end temperature of cold end surface S1 of cooling element 140. Temperature sensing unit 152 may be disposed at any location where the cold end temperature of cold end surface S1 may be sensed. For example, in the embodiment of fig. 2, the temperature sensing unit 152 may be disposed on the carrier plate 111 at a position adjacent to the metal heat conducting block 112 (e.g., position P1), or disposed on the metal heat conducting block 112 (e.g., position P2), or disposed on the cold end surface S1 (e.g., position P3), or disposed at another position adjacent to the cold end surface S1. In addition, the temperature and humidity sensing unit 151 and the temperature sensing unit 152 may be formed as a single body and disposed adjacent to the cooling element 140. Alternatively, when the cooling element 140 has a temperature sensor built therein, the temperature sensing unit 152 may also be a temperature sensor built in the cooling element 140, so as to more accurately measure the temperature of the cold end surface S1 of the cooling element 140.

On the other hand, in one embodiment, the active dehumidification unit 160 includes a physical adsorption type dehumidification element or a refrigeration type dehumidification element, which can be used to remove moisture in the environment to reduce the humidity of the environment. For example, the physical adsorption type dehumidifying element absorbs moisture by using a substance capable of absorbing moisture to reduce the ambient humidity, and the refrigeration type dehumidifying element can condense and discharge the moisture by forming a temperature difference through a refrigeration method of an electronic chip or a refrigeration method of refrigerant dehumidification to reduce the ambient humidity. Further, the active dehumidification unit 160 can communicate with the outside of the closed accommodating space CA, so that the active dehumidification unit 160 can discharge the water stored in the active dehumidification unit 160 after dehumidification. In addition, under this configuration, when the active dehumidification unit 160 needs to recover the dehumidification capability of the physisorption dehumidification element, the water vapor adsorbed by the physisorption dehumidification element can be dissipated to the outside of the closed accommodation space CA by means of heating, so as to recover the dehumidification capability thereof.

In one embodiment, the control unit 170 is coupled to the light valve module 110, the brightness sensing unit 130, the cooling element 140, the temperature and humidity sensing unit 151, the temperature sensing unit 152, the active dehumidification unit 160, and the light source 120. The control unit 170 is, for example, a Central Processing Unit (CPU), or other programmable general purpose or special purpose micro control unit 170 (MCU), a microprocessor (microprocessor), a Digital Signal Processor (DSP), a programmable controller, an Application Specific Integrated Circuit (ASIC), a Graphics Processing Unit (GPU), an Arithmetic Logic Unit (ALU), or other similar elements or combinations thereof, which are not limited by the present invention.

In this embodiment, the control unit 170 may be coupled to the specification temperature information obtaining unit. The specification temperature information obtaining unit may be used to obtain specification temperature information, and the control unit 170 may obtain the specification temperature of the cooling element 140 based on the specification temperature information. Specifically, the specification temperature may be used to determine whether the cold end temperature of the cold end surface S1 of the cooling element 140 is too high, and when the cold end temperature of the cooling element 140 is higher than the specification temperature, it represents that the ambient temperature of the heating element is higher than the upper limit temperature at which the heating element can operate normally. That is, the cooling element 140 can remove less heat from the heat generating element than the heat generated by the heat generating element, which may affect the performance of the projection apparatus 100. That is, the specification temperature information is used as the basis for obtaining the specification temperature, which can reflect the upper limit temperature of the heating element in normal operation.

More specifically, in the embodiment, the light valve module 110 is a heating element, and the heat generated by the light valve module 110 increases with the increase of the brightness, so the working efficiency of the cooling element 140 also needs to increase, and the heat is carried away in time. Therefore, the cooling efficiency required by the cooling element 140 to dissipate heat of the light valve module 110 can be adjusted according to the brightness sensed by the brightness sensing unit 130 or the brightness of the light source 120. In the present embodiment, the control unit 170 can determine the specification temperature of the cooling element 140 according to the brightness sensed by the brightness sensing unit 130. That is, in the present embodiment, the brightness sensing unit 130 is a specification temperature information obtaining unit, and the brightness is specification temperature information.

For example, fig. 3 is a schematic diagram illustrating a relationship between the specification temperature and the brightness according to an embodiment of the present invention. Referring to fig. 3, different brightness intervals correspond to different specification temperatures. The control unit 170 may determine the corresponding specification temperature according to the brightness interval sensed by the brightness sensing unit 130. In the example of fig. 3, when the brightness sensed by the brightness sensing unit 130 is the first brightness value B1, the control unit 170 may determine that the specification temperature is the first temperature value TS 1. When the brightness sensed by the brightness sensing unit 130 is the second brightness value B2 greater than the first brightness value B1, the control unit 170 may determine that the specification temperature is the second temperature value TS2 less than the first temperature value TS 1.

However, in another embodiment, the control unit 170 may also determine the specification temperature by using a table lookup. For example, table 1 is an example of the relationship between specification temperature and brightness. The control unit 170 can obtain the brightness according to table 1, and then obtain the specification temperature of the cooling element 140 based on the brightness table. In this embodiment, the specification temperature information obtaining unit can be omitted, and the specification temperature information is the operating temperature information of the light source 120, such as the brightness.

Luminance (lumen)	Specification temperature (. degree. C.)
		12000	39
15000	35
		18000	31
21000	27
		24000	23
27000	20
		30000	16

TABLE 1

Table 1 and fig. 3 are only exemplary and are not intended to limit the present invention.

In an embodiment, after obtaining the specification temperature, the control unit 170 may calculate the dew point temperature according to the ambient temperature sensed by the temperature and humidity sensing unit 151 and the sensed ambient humidity. The dew point temperature is a critical temperature at which water in the ambient air condenses from a gaseous state to a liquid state, in other words, when the ambient temperature is lower than the dew point temperature, dew condensation may occur. Accordingly, the control unit 170 may determine whether to turn on or off the active dehumidification unit 160 or further adjust the power of the refrigeration element 140 according to the dew point temperature, the specification temperature and the cold end temperature of the refrigeration element 140, so as to prevent the condensation of the refrigeration element 140.

Fig. 4 is a flowchart illustrating a heat dissipation control method according to an embodiment of the present invention, wherein the heat dissipation control method can be implemented by the components of the projection apparatus 100 shown in fig. 1. Referring to fig. 1 and fig. 4, the following describes detailed steps of the heat dissipation control method of the present embodiment in combination with various elements of the projection apparatus 100 in fig. 1.

In one embodiment, step S00 and step S110 are executed, the projection apparatus 100 starts to start, and the control unit 170 determines the specification temperature of the cooling element 140 according to the specification temperature information. In the present embodiment, the control unit 170 determines the specification temperature of the cooling device 140 according to the brightness sensed by the brightness sensing unit 130, that is, the brightness sensing unit 130 is a specification temperature information obtaining unit, and the brightness is specification temperature information. As previously described, the specification temperature may be used to determine whether the cold end temperature of cold end surface S1 of refrigeration element 140 meets requirements. If the cold end temperature of the cooling element 140 is higher than the specification temperature, it represents that the ambient temperature of the heating element is higher than the upper limit temperature at which the heating element can normally operate, and at this time, the power of the cooling element 140 needs to be increased to improve the heat dissipation capability, thereby reducing the cold end temperature.

In the present embodiment, step S120 is executed, and the control unit 170 senses the ambient temperature and the ambient humidity in the enclosed accommodating space CA by the temperature and humidity sensing unit 151, and calculates the dew point temperature according to the ambient temperature and the ambient humidity. The dew point temperature is a critical temperature at which water in the ambient air condenses into a liquid state from a gaseous state, in other words, when the cold end temperature of the cold end surface S1 of the refrigerant element 140 is less than the dew point temperature, dew condensation may occur.

In the present embodiment, step S130 is executed, and the control unit 170 obtains the cold end temperature of the cold end surface S1 of the cooling element 140 by the temperature sensing unit 152. Specifically, after the projection apparatus 100 is started, the temperature of the light valve module 110 serving as the heating element gradually rises, and when the temperature sensing unit 152 senses that the cold end temperature has reached the starting temperature point, or after the control unit 170 determines that the cold end temperature rises to reach the specification temperature, the control unit 170 may start the cooling element 140 to dissipate heat of the heating element (e.g., the light valve module 110), so that the temperature of the light valve module 110 serving as the heating element gradually falls.

In the present embodiment, step S140 is executed, and the control unit 170 determines whether to turn on or off the active dehumidification unit 160 according to the dew point temperature, the specification temperature, and the cold end temperature. Specifically, as shown in fig. 4, in the present embodiment, step S140 includes a plurality of steps S141 to S149.

Further, as shown in fig. 4, in the present embodiment, in step S141, the control unit 170 determines whether the cold end temperature is less than the specification temperature. Specifically, if the cold end temperature is lower than the specification temperature, it represents that the light valve module 110 currently serving as the heating element is in an environment condition capable of operating normally. In this case, the control unit 170 may increase the power of the light source 120 to increase the brightness of the illumination beam of the light source 120. Alternatively, the control unit 170 may maintain the power of the light source 120 to maintain a certain brightness of the illumination beam. Under the condition that the illumination light beam maintains a certain brightness, the control unit 170 may further determine whether to adjust the power of the cooling element 140 or to turn off the active dehumidification unit 160, so as to save power and avoid the condensation phenomenon of the cooling element 140.

For example, in one embodiment, when the control unit 170 determines that the cold end temperature is less than the specification temperature in step S141, step S142 is executed to determine whether the cold end temperature is less than or equal to the dew point temperature. When the control unit 170 determines that the cold-side temperature is less than or equal to the dew-point temperature, it represents that the condensation phenomenon may occur in the cooling element 140. Therefore, the control unit 170 may adjust the power of the cooling element 140 to be decreased (step S143), so as to increase the ambient temperature to be greater than the dew point temperature to prevent the dew condensation. Furthermore, power can be saved by turning down the cooling device 140. Then, the process may return to step S110 to continuously monitor the dew point temperature, specification temperature, and cold end temperature of the projection apparatus 100 to avoid condensation.

On the other hand, in an embodiment, in step S142, when the control unit 170 determines that the cold end temperature is greater than the dew point temperature, step S144 is executed to turn off the active dehumidification unit 160, so as to save power, and the process returns to step S110 again. Specifically, when the cold end temperature is greater than or equal to the dew point temperature, it represents that the projection apparatus 100 is in a normal operation state at present, and therefore, the active dehumidification unit 160 does not need to be turned on to reduce the ambient humidity, and the active dehumidification unit 160 can be turned off to save the power.

On the other hand, in step S141, when the control unit 170 determines that the cold end temperature is greater than or equal to the specification temperature, it represents that the cold end temperature of the refrigeration element 140 needs to be decreased. Accordingly, step S145 is performed, and the control unit 170 determines whether or not the cooling element 140 is at the maximum power upper limit during operation. If the control unit 170 determines "no", step S146 is executed to increase the power of the refrigeration element 140 to further decrease the cold end temperature of the refrigeration element 140.

In one embodiment, step S147a is executed, and the control unit 170 determines whether the cold end temperature is less than or equal to the dew point temperature. If the judgment result is yes, it means that condensation may occur in the cooling element 140. In this case, the cold end temperature needs to be further reduced to meet the requirement of the specification temperature, so step S148 is performed to start the active dehumidification unit 160 for dehumidification to reduce the dew point temperature.

For example, fig. 5 is a schematic diagram illustrating a relationship between a dew point temperature and an environmental condition according to an embodiment of the present invention. Referring to fig. 5, when the ambient temperature in the closed accommodating space CA where the refrigeration device 140 and the light valve module 110 are located is 35 ℃, and the relative humidity is 80%, the dew point temperature at this time is 31 ℃ as shown in fig. 5.

Further, if the brightness (specification temperature information) requirement is set to 27000 lumens, the specification temperature is 20 ℃ as shown in Table 1. When the heating element is cooled using the cooling element 140 so that the temperature of the heating element reaches the specification temperature (20 ℃), since the specification temperature (20 ℃) is lower than the dew point temperature (31 ℃), the condensation phenomenon may occur. In one embodiment, step S148 is executed to turn on the active dehumidification unit 160 to reduce the ambient humidity. For example, when the ambient humidity is reduced to 40% (relative humidity), the dew point temperature is 19 ℃ when the ambient temperature in the closed accommodating space CA is 35 ℃. In this way, when the heating element is cooled by the cooling element 140 so that the temperature of the heating element reaches the specification temperature (20 ℃), dew condensation can be avoided because the specification temperature (20 ℃) is higher than the dew point temperature (19 ℃). It should be noted, however, that the above numerical ranges are only examples and are not intended to limit the present invention.

As shown in fig. 4, after step S148 is executed, the process may return to step S110 to continue the monitoring state. In addition, it is noted that in step S148, if the active dehumidification unit 160 dehumidifies by the physisorption type dehumidification element, after the active dehumidification unit 160 is turned on, the control unit 170 determines whether the ambient humidity in the enclosed accommodating space CA is decreased according to the sensing result of the temperature and humidity sensing unit 151, and when the ambient humidity in the enclosed accommodating space CA is not decreased, the physisorption type dehumidification element needs to be isolated from the air in the enclosed accommodating space CA, and the physisorption type dehumidification element needs to be internally dehumidified to recover the dehumidification capability of the physisorption type dehumidification element.

Further, as shown in fig. 4, when the control unit 170 determines "no" in step S147a, it means that the condensation phenomenon does not occur in the cooling element 140, and therefore step S149 is executed to turn off the active dehumidification unit 160 and return the flow to the continuous monitoring state in step S110.

On the other hand, as shown in fig. 4, if the control unit 170 determines that the power of the refrigeration element 140 is the maximum power of the refrigeration element 140 (i.e., if yes) in step S145, step S147b is executed to further determine whether the cold end temperature is less than or equal to the dew point temperature. In step S147b, when the control unit 170 determines that the cold end temperature is less than or equal to the dew point temperature, step S148 is executed to turn on the active dehumidification unit 160 for dehumidification so as to reduce the dew point temperature. On the other hand, in step S147a, when the control unit 170 determines "no", it determines to execute step S149, turns off the active dehumidification unit 160, and returns the process to the continuous monitoring state in step S110.

In this way, in the projection apparatus 100 and the heat dissipation control method of the present invention, by configuring the active dehumidification unit 160, it can be determined whether to open or close the active dehumidification unit 160 or adjust the power of the refrigeration element 140 according to the dew point temperature, the specification temperature and the cold end temperature. In this way, the projection apparatus 100 can prevent the condensation of the cooling element 140. Further, when the cold end temperature is lower than the specification temperature and the cold end temperature is lower than the dew point temperature, the power of the refrigeration element 140 can be reduced, so that the effects of saving electricity and avoiding condensation are achieved.

Fig. 6 is a schematic view of another projection apparatus according to an embodiment of the present invention. Referring to fig. 6, a projection apparatus 600 of the present embodiment is similar to the projection apparatus 100 of fig. 1, and the differences are as follows. Referring to fig. 6, in the present embodiment, the cold end surface S1 of the cooling element 140 is connected to the light source 620 for dissipating heat of the light source 620, in other words, in the present embodiment, the light source 620 is a heating element. For example, in the present embodiment, the light source 620 is a solid-state light source. Moreover, the connection manner of the cooling element 140 and the light source 620 is similar to the connection manner of the cooling element 140 and the light valve module 110 of the projection apparatus 100 in fig. 1, and is not repeated herein. Also, in the present embodiment, since the light source 620 is a heat generating element, the specification temperature of the cooling element 140 depends on the light source 620. Specifically, the specification temperature of the cooling device 140 decreases as the brightness of the light source 620 increases, and in the present embodiment, the specification temperature information obtaining unit may be omitted, and the specification temperature information is the operating temperature information of the light source 120, such as the brightness.

As shown in fig. 6, in the present embodiment, since the light source 620 is a heating element, the isolation layer IL is used to form a closed accommodating space CA, and the light source 620, the cooling element 140, the temperature and humidity sensing unit 151, the temperature sensing unit 152 and the active dehumidification unit 160 as the heating element are located in the closed accommodating space CA, and the relative position configuration relationship thereof is also similar to that of fig. 1, and is not repeated herein.

Thus, in the above configuration, the heat dissipation control method of fig. 4 can also be executed by the projection apparatus 600 to dissipate heat of the light source 620 and avoid condensation, so as to achieve functions and advantages similar to those of the projection apparatus 100, which is not described herein again. In addition, in the embodiment, the temperature of the light source 620 is below the specification temperature, so that the increase of the light emitting efficiency of the light source 620 can be avoided, the number of the elements of the light source 620 is reduced, and the cost of the light source 620 is greatly reduced.

In summary, the embodiments of the present invention have at least one of the following advantages or effects. The projection device and the heat dissipation control method of the present invention can determine whether to open or close the active dehumidification unit or adjust the power of the refrigeration element according to the dew point temperature, the specification temperature and the cold end temperature by the active dehumidification unit. Thus, dew condensation can be avoided. Moreover, under the condition that the cold end temperature is lower than the specification temperature, even if the cold end temperature is also lower than the dew point temperature, the projection device can adjust and reduce the power of the refrigerating element under the condition that the active dehumidifying unit is not started, so that the effects of saving electricity and avoiding the condensation phenomenon of the refrigerating element are achieved at the same time.

However, the above description is only a preferred embodiment of the present invention, and the scope of the present invention should not be limited thereto, and all the simple equivalent changes and modifications made according to the claims and the contents of the present invention are still included in the scope of the present invention. Moreover, it is not necessary for any embodiment or claim to address all of the objects, advantages, or features disclosed herein. In addition, the abstract and the utility model name are only used for assisting the retrieval of patent documents and are not used for limiting the scope of the invention. Furthermore, the terms "first", "second", and the like in the description or the claims are used only for naming elements (elements) or distinguishing different embodiments or ranges, and are not used for limiting the upper limit or the lower limit on the number of elements.

Description of reference numerals:

100. 600: projection device

110: light valve module

111: support plate

112: heat-conducting metal block

113: heat radiation module

120. 620: light source

130: brightness sensing unit

140: refrigeration element

151: temperature and humidity sensing unit

152: temperature sensing unit

160: active dehumidification unit

170: control unit

180: projection lens module

190: optical-mechanical module

B1, B2: brightness value

CA: closed containing space

H1: casing (CN)

IL: insulating layer

P1, P2, P3: position of

S1: cold end surface

S2: hot end surface

TS1, TS 2: temperature value

S00, S110, S120, S130, S140, S141, S142, S143, S144, S145, S146, S147a, S147b, S148, S149: step (ii) of

W1: an air inlet.

Claims

1. A projection device is characterized in that the projection device is provided with a closed accommodating space and comprises a heating element, a refrigerating element, an active dehumidification unit, a specification temperature information acquisition unit, a temperature and humidity sensing unit, a temperature sensing unit and a control unit, wherein:

the refrigeration element has a cold end surface and a hot end surface, wherein the cold end surface is used for radiating the heating element;

the heating element, the refrigerating element and the active dehumidifying unit are positioned in the closed accommodating space;

the specification temperature information obtaining unit is used for obtaining specification temperature information;

the temperature and humidity sensing unit senses the ambient temperature and the ambient humidity in the closed accommodating space;

the temperature sensing unit senses a cold end temperature of the cold end surface; and

the control unit is coupled with the specification temperature information acquisition unit, the temperature and humidity sensing unit, the temperature sensing unit, the active dehumidification unit, the refrigeration element and the heating element, the control unit determines the specification temperature of the refrigeration element according to the specification temperature information and calculates the dew point temperature according to the environment temperature and the environment humidity, wherein the dew point temperature is calculated according to the environment temperature and the environment humidity

And the control unit judges whether to open or close the active dehumidification unit according to the dew point temperature, the specification temperature and the cold end temperature.

2. The projection device of claim 1, wherein the control unit determines whether the cold end temperature is less than or equal to the dew point temperature when the cold end temperature is less than the specification temperature, reduces the power of the refrigeration element when the cold end temperature is less than or equal to the dew point temperature, and turns off the active dehumidification unit when the cold end temperature is greater than the dew point temperature.

3. The projection apparatus according to claim 1, wherein when the cold-end temperature is equal to or higher than the specification temperature, the control unit determines whether the cooling element is at an upper maximum power limit when operating, and when the cooling element is not at the upper maximum power limit when operating, the control unit increases the power of the cooling element.

4. The projection apparatus according to claim 3, wherein after the control unit adjusts the power of the cooling element, the control unit determines whether the cold end temperature is less than or equal to the dew point temperature, when the cold end temperature is less than or equal to the dew point temperature, the control unit turns on the active dehumidification unit for dehumidification, and when the cold end temperature is greater than the dew point temperature, the control unit turns off the active dehumidification unit.

5. The projection apparatus according to claim 3, wherein when the control unit determines that the cooling element is at the maximum power upper limit during operation, the control unit determines whether the cold end temperature is less than or equal to the dew point temperature, when the cold end temperature is less than or equal to the dew point temperature, the control unit turns on the active dehumidification unit for dehumidification, and when the cold end temperature is greater than the dew point temperature, the control unit turns off the active dehumidification unit.

6. The projection device of claim 1, wherein the active dehumidification unit comprises a physisorption dehumidification element or a refrigeration dehumidification element.

7. The projection apparatus according to claim 6, wherein the control unit turns on the active dehumidifying unit, and when the active dehumidifying unit includes the physical adsorption dehumidifying element, after the active dehumidifying unit is turned on, the control unit determines whether the ambient humidity in the enclosed accommodating space is decreased, and when the ambient humidity in the enclosed accommodating space is not decreased, the control unit isolates the physical adsorption dehumidifying element from the air in the enclosed accommodating space, and performs internal dehumidification on the physical adsorption dehumidifying element to recover the dehumidifying capability of the physical adsorption dehumidifying element.

8. The projection device of claim 1, further comprising:

a light valve module; and

a light source providing an illumination beam to the light valve module.

9. The projection apparatus according to claim 8, wherein the heating element is the light valve module of the projection apparatus, the specification temperature information obtaining unit is a brightness sensing unit, the brightness sensing unit is disposed beside a transmission path of the illumination beam, senses brightness of the illumination beam, and the brightness is the specification temperature information, and the control unit determines the specification temperature of the cooling element according to the brightness of the illumination beam.

10. The projection apparatus according to claim 8, wherein the heating element is the light source of the projection apparatus, and the specification temperature information is operating temperature information of the light source, and the control unit determines the specification temperature of the cooling element based on the operating temperature information of the light source.

11. The projection device of claim 1, further comprising:

the isolation layer is used for forming the closed accommodating space; and

the casing comprises an air inlet, and the air inlet is adjacent to the closed accommodating space.

12. The projection apparatus according to claim 1, wherein the temperature and humidity sensing unit and the temperature sensing unit are adjacent to the cooling element, and the temperature and humidity sensing unit and the temperature sensing unit are integrally formed.

13. The projection device of claim 1, further comprising:

a heat dissipation module, wherein the cold side surface of the cooling element is configured to the heat generating element in a thermally conductive manner, and the hot side surface of the cooling element is configured to the heat dissipation module in a thermally conductive manner.

14. The projection apparatus according to claim 1, wherein after the control unit determines that the cold end temperature rises to reach the specification temperature, the control unit activates the cooling element to dissipate heat from the heating element.