l3〇45j2 九、發明說明： 【發明所屬之技術領域】 战本發明係關於一種擺動裝置，特別關於一種應用於光 子繞碩組之擺動裝置。 【先前技術】L3〇45j2 IX. Description of the invention: [Technical field to which the invention pertains] The invention relates to a swinging device, and more particularly to a swinging device applied to a photon winding group. [Prior Art]
由於大顯示面積、小型化，以及輕量化系統的多重需 求 ’影像投影系統成為目前光電產業中最熱門的項目之 ，“ 現今，依據投影的原理主要可以將投影系統分為三大 貝分別為液晶投影系統（liquid crystal display，LCD )、 單晶石夕液晶投影系統（liquid crystal on silicon, LCOS )，以 及數位光源處理器投影系統（digital light processing， dlp ) ’其中dlp具有高亮度、正確地色調重現性、快速 的反應時間、無雜訊，以及輕薄短小等優點，因而成為目 Φ 前新一代熱門的投影系統之一。 〜 如圖1所示，在DLP式投影系統1中，係採用數位控 ‘ 制’利用反射光原理’將來自光源11之光聚集之後，經 由透鏡12聚焦’再穿過紅綠藍三色的彩色濾光片13後， 投射至數位微鏡日日片（digital micrchmirror device，DMD) 14上。由於·，數位微鏡晶片14上具有許多微小的可動鏡 片，經由驅動電極控制可動鏡片傾斜角度以及偏轉時間， 再藉由切換光的反射方向由光學鏡頭組15投射至螢幕16 成像。 6 1304513 此外，請同時參閱圖1及圖2,光學鏡頭組15中具有 :擺動裝置20，且擺動裝置20具有二磁性元件21、一遮 光元件22、一驅動迴路23，以及一彈性元件24。各磁性 元件21係分別為一板狀磁鐵，遮光元件22係樞設於光學 鏡頭纟且15上，且遮光元件22之一端係具有一遮光部221， 而驅動趣路23係設置於遮光元件22上且位於相對於遮光 部221之一端。彈性元件24係為一扭簧，係位於遮光元 φ 件22樞設於光學鏡頭組15處。當驅動迴路23開啟時， 驅動迴路23係產生磁場感應而與磁性元件21相互吸引， 俾使遮光元件22於一開啟位置pi與一遮光位置P2來回 擺動（如圖3所示）。如此一來，遮光元件22即可控制光 ^通1 ’以使晝面更具有色彩層次感，也使得晝面之灰階顯 色度更佳。當驅動迴路23關閉時，彈性元件24係提供一 回復力係使遮光元件22移至一停駐位置P3(如圖3所示）。 然而，經過一段時間使用之後，彈性元件24可能會 φ 發生彈性疲乏之情事，使得遮光元件22無法穩固地定位， ' 使得移動光學鏡頭組15時，遮光元件22則容易晃動，而 - 造成光學鏡頭組内部其他元件之損壞。此外，若彈性元件 24之彈性係數太小時，驅動迴路23驅動遮光元件22偏擺 之作用力可能造成彈性元件24損壞，而使得彈性元件24 失去將遮光元件22定位於開啟位置之功用。另外，若將 彈性元件24之彈性係數增加，以改善驅動迴路23之作用 力造成彈性元件24損壞之問題，以及曰後彈性元件％彈 性疲乏之疑慮，但是，卻使得驅動迴路23必須消耗較大 1304513 之電能，方能驅動遮光元件 便，而有待改進。 22作動，確實造成相當之不 【發明内容】 电及述課題’本發R目料提供—種光學鏡頭 置’能於驅動迴路不作動時，有效地固定遮 蔽兀件，且具有較不消耗電能之優點。 於一 上述目=’依本發明之擺動装置，係設置 二遮= 擺動裝置包含二磁性元件、 迴路，以及1磁元件。二磁性元件 係王千仃&置。遮光元件之1係為—遮件 體且位於二磁性元件之間。驅動迴路;設置於 j兀件相對遮光部之—端，驅動迴路具有 件且鄰設驅動趣路，當驅動一 ，㈣遮光部固定於一 :駐驅動迴路開啟時’線圈係受磁場感應而與磁 輪流吸弓丨’俾使遮光部於-開啟位置與-遮 光位置間偏擺。 為達上述目白勺*本發明之光學鏡頭組，包含一殼 &複數鏡片，以及-擺動裝置。複數鏡片係設置於殼體 :。擺動裝置係設置於殼體内，擺動裝置包含二磁性元 件、-遮光元件、1_迴路H導磁元件。二磁性 兀件係壬平订設置。遮光元件之〜端係為一遮光部，遮光 凡件係樞設於殼體且位於二磁性元件之間。驅動迴路係設 1304513 置於遮光元件相對遮光部之一端，驅動迴路具有一線圈。 導磁元件設置於遮光元件且鄰設驅動迴路，當驅動迴路關 閉時，導磁元件係受二磁性元件吸引，而將遮光部固定於 一停駐位置，當驅動迴路開啟時，線圈係受磁場感應而與 磁性元件二端之磁極輪流吸引，俾使遮光部於一開啟位置 與一遮光位置間偏擺。 承上所述，依因本發明之光學鏡頭組及其擺動裝置， 係利用導磁元件與磁性元件相吸引之特性，使得遮光元件 B 得以於驅動迴路關閉時穩固地定位於停駐位置，如此一 來，即可避免習用結構中，因為遮光元件定位不良，而造 ' 成光學鏡頭組内部其他元件損壞之疑慮。此外，由於導磁 - 元件之設置，在設計驅動迴路時，並不需要加以大量之電 流方能驅動遮光元件偏擺，確實具有節省電能消耗之優 點，具有良好之產業利用性。 【實施方式】 ^ 以下將參照相關圖式，說明依本發明若干較佳實施例 、 之光學鏡頭組及其擺動裝置。 首先，請參閱圖4至圖7,係用以說明本發明第一實 施例之擺動裝置30。如圖4所示，擺動裝置30係設置於 一光學鏡頭組3之一殼體40。殼體40具有一光通道41， 一光線L係通過光通道41内之複數鏡片50而投射於一螢 幕（圖中未示）成像。如圖5至圖7所示，擺動裝置30 包含二磁性元件31、一遮光元件3 2、一驅動迴路3 3，以 9 1304513 及一導磁元件34。 如圖7所示，磁性元件31係呈平行設置，本實施例 中，各磁性元件31係呈板狀，而呈上下平行並列，且各 磁性元件31同側之磁極極性係呈相反設置。 遮光元件32之一端係為一遮光部321，且遮光元件 32係樞設於殼體40並位於二磁性元件31之間。本實施例 中，遮光元件32係由塑膠所製成，除此之外，遮光元件 32亦可以鋁或是其他非磁性材質所製成。 驅動迴路33係設置於遮光元件32相對遮光部321之 一端，且驅動迴路33具有一線圈331。當驅動迴路33啟 " 動時，交流電流入線圈331產生磁場，俾使線圈331受磁 - 場感應而與磁性元件31二端之磁極輪流吸引，俾使遮光 部321於一開啟位置P1 (如圖5與圖7所示）與一遮光位 置P2 (如圖6與圖7所示）間偏擺。 導磁元件34係設置於遮光元件32且鄰設於驅動迴路 p 33，當驅動迴路33關閉時，導磁元件34係受磁性元件31 ， 之吸引，而將遮光元件32固定於一停駐位置P3 (如圖7 . 所示）。本實施例中，導磁元件34係為一塊體，其材質係 為鐵所製成，當然，導磁元件34亦可以鈷或鎳等磁性材 質製成。此外，如圖7所示，本實施例中，遮光元件32 由左至右之偏擺位置係分別為停駐位置P3、開啟位置P2 及遮光位置P1，當然，設計的過程之中，亦可採取將停駐 位置P3與開啟位置P2或遮光位置P1於相同位置設置。 請參閱圖5至圖7所示，說明依據本實施例中，擺動 1304513 裝置30之作動方式。 如圖5與圖6所示，此時，驅動迴路33係呈開啟之 狀態，依據線圈331通電狀態之改變，於是，線圈331產 生磁場感應而與磁性元件31二端之磁極輪流吸引，使得 遮光部321於開啟位置P1與遮光位置P2間偏擺。倘若關 閉驅動迴路33，於線圈331在不通電之狀態下，線圈331 係不與磁性元件31吸引，於是，導磁元件34則與磁性元 件31相吸引，而將遮光元件32穩固定位於停駐位置P3 *(如圖7所示）。欲使遮光元件32再次偏擺，係開啟驅動 迴路33,且驅動迴路33與磁性元件31間之磁力係大於導 • 磁元件34與磁性元件31間之磁力，如此一來即可驅使遮 • 光元件32於開啟位置P1與遮光位置P2間偏擺。 經由本發明可知，當驅動迴路33開啟時，遮光元件 32係於開啟位置P1與遮光位置P2間偏擺，當驅動迴路 33關閉時，導磁元件34係受到磁性元件31之吸引，而將 _ 遮光元件32穩固地定位於停駐位置P3，本發明係利用導 - 磁元件34與磁性元件31相吸之原理，取代習用結構中彈 . 性元件之結構，同樣具有將遮光元件32定位於停駐位置 P3之功用。此外，欲開啟驅動迴路33時，也不需要耗費 太多之電能，即可帶動遮光元件32偏擺，相較習用結構 而言，本發明之擺動裝置30確實具有能穩固定位遮光元 件32，以及具有較不消耗電能之優點。 請參閱圖8,係為本發明第二較佳實施例之擺動裝置 30，同樣地，擺動裝置30包含二磁性元件31、一遮光元 11 1304513 件32、一驅動迴路33，以及一導磁元件35。其中，磁性 元件31、遮光元件32、驅動迴路33之結構與功效與前揭 實施例相同，在此給於相同標號，且容不贅述。 本實施例中，導磁元件35係為一磁鐵，係設置於驅 動迴路33之一側，當驅動迴路33關閉時，導磁元件35 係與磁性元件31相互吸引，而將遮光元件32穩固定位於 一停駐位置P3 (如圖七所示）。 此外，導磁元件3 5亦可為一線圈（圖中未示），當驅 > 動迴路33關閉時，導磁元件35係接收一外部電流（圖中 未示），使得導磁元件35產生磁場感應而與磁性元件31 ’ 吸引，而將遮光元件32定位於停駐位置P3。 • 請參閱圖4所示，係為本發明第三實施例之光學鏡頭 組3，包含一殼體40、複數鏡片50，以及一擺動裝置30。 殼體40具有一光通道41，光線L係通過光通道41而投射 於一螢幕（圖中未示）成像。複數鏡片50係分別設置於 _ 殼體40之一端，由於鏡片50之設置方式並非本發明之重 • 點，在此容不贅述。擺動裝置30之組件結構、連結關係， .以及作動方式係與前揭實施例相同，在此給予相同標號且 容不贅述。 承上所述，依因本發明之光學鏡頭組及其擺動裝置， 係利用導磁元件與磁性元件相吸引之特性，使得遮光元件 得以於驅動迴路關閉時穩固地定位於停駐位置，如此一 來，即可避免習用結構中，因為遮光元件定位不良，而造 成光學鏡頭組内部其他元件損壞之疑慮。此外，由於導磁 12 1304513 元件之設置，在設計驅動迴路時，並不需要加以大量之電 流方能驅動遮光元件偏擺，確實具有節省電能消耗之優 點，具有良好之產業利用性。 以上所述僅為舉例性，而非為限制性者。任何未脫離 本發明之精神與範疇，而對其進行之等效修改或變更，均 應包含於後附之申請專利範圍中。 【圖式簡單說明】 B 圖1係為習知之DLP式投影系統之一示意圖； 圖2係為習知之擺動裝置之一示意圖； ， 圖3係為沿圖2中A-A剖線之一剖示圖； • 圖4係為本發明第一實施例之擺動裝置及第三實施例 之光學鏡頭組之一示意圖； 圖5係為本發明第一實施例之擺動裝置之另一示意 圖； B 圖6係為本發明第一實施例之擺動裝置之又一示意 * 圖， , 圖7係為沿圖4中B-B剖線之一剖示圖；以及 圖8係為本發明第二實施例之擺動裝置之一示意圖。 元件符號說明： I DLP式投影系統 II 光源 12 透鏡 13 1304513 13 彩色濾光片 14 數位微鏡晶片 15 光學鏡頭組 16 螢幕 20 擺動裝置 21 磁性元件 22 遮光元件 221 遮光部 23 驅動迴路 24 彈性元件 3 光學鏡頭組 30 擺動裝置 31 磁性元件 32 遮光元件 321 遮光部 33 驅動迴路 331 線圈 34 導磁元件 35 導磁元件 40 殼體 41 光通道 50 鏡片 A-A 直線 B-B 直線 1304513 L 光線 PI 開啟位置 P2 遮光位置 P3 停駐位置Due to the large display area, miniaturization, and multiple requirements of lightweight systems, the image projection system has become the hottest item in the optoelectronic industry. "Today, according to the principle of projection, the projection system can be divided into three big shells for liquid crystal projection. Liquid crystal display (LCD), liquid crystal on silicon (LCOS), and digital light processing (dlp) 'where dlp has high brightness and correct color tone The current, fast response time, no noise, and the advantages of lightness, thinness and shortness have become one of the popular projection systems of the previous generation. ~ As shown in Figure 1, in the DLP projection system 1, digital is used. The control system uses the principle of reflected light to collect the light from the light source 11 and then focus it through the lens 12 to pass through the color filter 13 of the red, green and blue colors, and then project it to the digital micromirror (digital micrchmirror). Device, DMD) 14. Since the digital micromirror wafer 14 has many tiny movable lenses, via the drive electrodes The tilt angle of the movable lens and the deflection time are then imaged by the optical lens group 15 to the screen 16 by the direction of the switching light. 6 1304513 In addition, please refer to FIG. 1 and FIG. 2 together, the optical lens group 15 has: a swing device 20, and the swinging device 20 has two magnetic elements 21, a light blocking element 22, a driving circuit 23, and an elastic element 24. Each of the magnetic elements 21 is a plate magnet, and the light blocking element 22 is pivotally disposed on the optical lens. And the upper end of the light-shielding member 22 has a light-shielding portion 221, and the driving fun circuit 23 is disposed on the light-shielding member 22 and located at one end of the light-shielding portion 221. The elastic member 24 is a torsion spring. The light shielding element φ 22 is pivoted at the optical lens group 15. When the driving circuit 23 is turned on, the driving circuit 23 generates magnetic field induction and attracts the magnetic element 21, so that the light shielding element 22 is in an open position pi and a light blocking position. P2 swings back and forth (as shown in Fig. 3). In this way, the light-shielding element 22 can control the light-passing 1' to make the kneading surface more color-layered, and also make the gray-scale color rendering of the kneading surface better. When the drive circuit 23 is closed, the resilient member 24 provides a restoring force to move the shutter member 22 to a park position P3 (shown in Figure 3). However, after a period of use, the spring member 24 may φ occur. The elastic fatigue causes the shading member 22 to be unable to be stably positioned, 'when the optical lens group 15 is moved, the shading member 22 is easily shaken, and - causing damage to other components inside the optical lens group. Further, if the elastic member 24 is elastic When the coefficient is too small, the force that the drive circuit 23 drives the yaw element 22 to yaw may cause damage to the elastic member 24, and the elastic member 24 loses the function of positioning the visor member 22 in the open position. In addition, if the elastic modulus of the elastic member 24 is increased to improve the damage of the elastic member 24 caused by the force of the driving circuit 23, and the problem that the elastic member of the rear elastic member is less elastic, the driving circuit 23 must be consumed more. The power of 1304513 can drive the shading element, and needs to be improved. 22 actuation, it does cause quite a difference [invention] The electric and the subject 'this R object supply provides - an optical lens set' can effectively fix the shielding element when the drive circuit is not actuated, and has less power consumption The advantages. In the above-mentioned object, the swinging device according to the present invention is provided with a two-shield = swinging device comprising two magnetic elements, a circuit, and a magnetic element. The two magnetic components are Wang Qianxi & The light-shielding element 1 is a cover body and is located between the two magnetic elements. The driving circuit is disposed at the end of the j-shaped member opposite to the light-shielding portion, and the driving circuit has a member and is adjacent to the driving fun circuit. When the driving is one, (4) the light-shielding portion is fixed to one: when the parking drive circuit is opened, the coil is magnetically induced and The magnetic wheel sucks the bow 丨 '俾 so that the light-shielding portion is yawed between the -open position and the -shielded position. In order to achieve the above object, the optical lens unit of the present invention comprises a shell & multiple lens, and a swinging device. The plurality of lenses are disposed in the housing: The oscillating device is disposed in the housing, and the oscillating device comprises two magnetic elements, a shading element, and a 1-circuit H magnetic conducting element. Two magnetic components are set in a flat setting. The end of the light-shielding element is a light-shielding portion, and the light-shielding member is pivotally disposed on the casing and located between the two magnetic elements. The driving circuit system 1304513 is placed at one end of the light shielding member opposite to the light shielding portion, and the driving circuit has a coil. The magnetic conductive component is disposed on the light shielding component and adjacent to the driving circuit. When the driving circuit is closed, the magnetic conductive component is attracted by the two magnetic components, and the light shielding portion is fixed to a parking position. When the driving circuit is opened, the coil is subjected to a magnetic field. Inductively and magnetically attracted to the magnetic poles at both ends of the magnetic element, so that the light shielding portion is yawed between an open position and a light blocking position. According to the above, the optical lens assembly and the swinging device thereof according to the present invention utilize the characteristics that the magnetic conductive member and the magnetic member are attracted, so that the light shielding member B can be stably positioned at the parking position when the driving circuit is closed. As a result, the conventional structure can be avoided, because the shading element is poorly positioned, and the other components inside the optical lens group are damaged. In addition, due to the magnetic permeability-component arrangement, it is not necessary to apply a large amount of current to drive the shading of the shading element when designing the driving circuit, which has the advantage of saving power consumption and has good industrial applicability. [Embodiment] Hereinafter, an optical lens group and a swinging device thereof according to preferred embodiments of the present invention will be described with reference to the related drawings. First, please refer to Figs. 4 to 7 for explaining the swinging device 30 of the first embodiment of the present invention. As shown in Fig. 4, the swinging device 30 is disposed in a casing 40 of an optical lens group 3. The housing 40 has a light path 41 through which a light L is projected through a plurality of lenses 50 in the light path 41 and projected onto a screen (not shown). As shown in FIG. 5 to FIG. 7, the swinging device 30 includes two magnetic elements 31, a light blocking element 32, a drive circuit 33, a 91304513 and a magnetic conductive element 34. As shown in Fig. 7, the magnetic elements 31 are arranged in parallel. In the present embodiment, each of the magnetic elements 31 has a plate shape and is juxtaposed in parallel in the up and down direction, and the magnetic pole polarities on the same side of the respective magnetic elements 31 are oppositely arranged. One end of the light shielding member 32 is a light shielding portion 321 , and the light shielding member 32 is pivotally disposed on the housing 40 and located between the two magnetic members 31 . In this embodiment, the light shielding member 32 is made of plastic. In addition, the light shielding member 32 can also be made of aluminum or other non-magnetic materials. The drive circuit 33 is disposed at one end of the light shielding member 32 with respect to the light shielding portion 321, and the drive circuit 33 has a coil 331. When the drive circuit 33 is activated, the alternating current enters the coil 331 to generate a magnetic field, so that the coil 331 is magnetically induced by the magnetic field and is attracted to the magnetic poles at both ends of the magnetic element 31, so that the light shielding portion 321 is in an open position P1 ( Between FIG. 5 and FIG. 7) and a light-shielding position P2 (shown in FIGS. 6 and 7) are yawed. The magnetic conductive element 34 is disposed on the light shielding element 32 and adjacent to the driving circuit p 33. When the driving circuit 33 is closed, the magnetic conductive element 34 is attracted by the magnetic element 31, and the light blocking element 32 is fixed to a parking position. P3 (as shown in Figure 7.). In the present embodiment, the magnetic conductive element 34 is a single body made of iron. Of course, the magnetic conductive element 34 can also be made of a magnetic material such as cobalt or nickel. In addition, as shown in FIG. 7 , in the present embodiment, the left-to-right yaw position of the shading element 32 is the parking position P3, the opening position P2, and the shading position P1, respectively. Of course, during the design process, The parking position P3 is set at the same position as the open position P2 or the light blocking position P1. Referring to FIG. 5 to FIG. 7, the operation mode of the device 130 for swinging 1304513 according to the present embodiment will be described. As shown in FIG. 5 and FIG. 6, at this time, the drive circuit 33 is in an open state, and according to the change of the energization state of the coil 331, the coil 331 generates magnetic field induction and attracts the magnetic poles at both ends of the magnetic element 31, so that the light is blocked. The portion 321 is yawed between the open position P1 and the light blocking position P2. If the drive circuit 33 is turned off, the coil 331 is not attracted to the magnetic element 31 when the coil 331 is not energized, so that the magnetic conductive element 34 is attracted to the magnetic element 31, and the light blocking element 32 is stably positioned at the stop. Position P3 * (as shown in Figure 7). To make the shading element 32 yaw again, the driving circuit 33 is turned on, and the magnetic force between the driving circuit 33 and the magnetic element 31 is greater than the magnetic force between the magnetic element 34 and the magnetic element 31, so that the light can be shielded. The element 32 is yawed between the open position P1 and the light blocking position P2. According to the present invention, when the drive circuit 33 is opened, the light shielding member 32 is yawed between the open position P1 and the light blocking position P2, and when the drive circuit 33 is closed, the magnetic conductive member 34 is attracted by the magnetic member 31, and The shading element 32 is stably positioned at the parking position P3. The present invention utilizes the principle that the guiding-magnetic element 34 and the magnetic element 31 are attracted to each other, instead of the structure of the elastic element in the conventional structure, and also has the positioning of the shading element 32. The function of station P3. In addition, when the driving circuit 33 is to be turned on, the shading device 32 can be driven to yaw without consuming too much electric energy. Compared with the conventional structure, the swinging device 30 of the present invention does have a stable fixing position shading member 32, and It has the advantage of less power consumption. Please refer to FIG. 8 , which is a swing device 30 according to a second preferred embodiment of the present invention. Similarly, the swing device 30 includes two magnetic elements 31 , a light shielding element 11 1304513 , a driving circuit 33 , and a magnetic conductive component . 35. The structure and function of the magnetic element 31, the light-shielding element 32, and the driving circuit 33 are the same as those of the previous embodiment, and the same reference numerals are used herein. In this embodiment, the magnetic conductive element 35 is a magnet disposed on one side of the drive circuit 33. When the drive circuit 33 is closed, the magnetic conductive element 35 and the magnetic element 31 are attracted to each other, and the light-shielding element 32 is fixed. Located at a parked position P3 (as shown in Figure 7). In addition, the magnetic conductive component 35 can also be a coil (not shown). When the drive circuit 33 is closed, the magnetic conductive component 35 receives an external current (not shown), so that the magnetic conductive component 35 Magnetic field induction is generated to attract the magnetic element 31', and the light blocking element 32 is positioned at the parked position P3. Referring to Fig. 4, an optical lens unit 3 according to a third embodiment of the present invention comprises a housing 40, a plurality of lenses 50, and a swinging device 30. The housing 40 has a light path 41 through which light L is projected by a screen (not shown). The plurality of lenses 50 are respectively disposed at one end of the housing 40. Since the arrangement of the lenses 50 is not the point of the present invention, it will not be described here. The component structure, the connection relationship, and the actuation mode of the oscillating device 30 are the same as those of the previous embodiment, and the same reference numerals will be given thereto. According to the above, the optical lens assembly and the swinging device thereof according to the present invention utilize the characteristics that the magnetic conductive member and the magnetic member are attracted, so that the light shielding member can be stably positioned in the parking position when the driving circuit is closed, such that In this case, the conventional structure can be avoided, because the shading component is poorly positioned, and the other components inside the optical lens group are damaged. In addition, due to the arrangement of the components of the magnetic conductive 12 1304513, it is not necessary to apply a large amount of current to drive the yaw of the shading element when designing the driving circuit, which has the advantage of saving power consumption and has good industrial applicability. The above is intended to be illustrative only and not limiting. Any equivalent modifications or alterations to the spirit and scope of the present invention are intended to be included in the scope of the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a conventional DLP projection system; FIG. 2 is a schematic diagram of a conventional swing device; FIG. 3 is a cross-sectional view taken along line AA of FIG. 4 is a schematic view of a swinging device according to a first embodiment of the present invention and an optical lens assembly of a third embodiment; FIG. 5 is another schematic view of the swinging device according to the first embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 7 is a cross-sectional view taken along line BB of FIG. 4; and FIG. 8 is a swing device according to a second embodiment of the present invention; A schematic diagram. Description of component symbols: I DLP projection system II Light source 12 Lens 13 1304513 13 Color filter 14 Digital micromirror wafer 15 Optical lens group 16 Screen 20 Swing device 21 Magnetic element 22 Shading element 221 Shading part 23 Driving circuit 24 Elastic element 3 Optical lens group 30 Swing device 31 Magnetic element 32 Light-shielding element 321 Light-shielding part 33 Driving circuit 331 Coil 34 Magnetic element 35 Magnetic element 40 Housing 41 Optical channel 50 Lens AA Straight line BB Straight 1304513 L Light PI Open position P2 Light-shielding position P3 Parking position