201219825 六、發明說明： 【發明所屬之技術領域】 本發明係與投影鏡頭有關，更詳而言之是指—種可變焦之 短焦投影鏡頭。 【先前技術】 隨著視訊技術的進步，咖於—般家庭空間之短焦投影機 • 越來越普及，其用以將影像清晰地呈_螢幕上之短焦投影鏡 頭更是達飾距投f彡的核响件之—。然而，f知之短焦投影 鏡頭大多皆不具奴距之魏，使得者在糊短紐 影機進行投斜，無法於蚊錄處依其f求進行投影之影像 大小調整，而必須將短焦投影機移動才可滿足調整之目的，徒 增使用者之不便。 另-方面’隨焦投影機所用之數錄鏡裝置陶如 φ Deviee ’ DMD) , ; (lc〇s —或液晶面板 (LCDpand)在提升像素之同時，亦朝小型化發展。相對應的， 短焦投影鏡頭在具有高絲效能之啊，_降低其大小及重 量’以使其雌狀織郷機_符合絲所植之輕量斑 便攜。而少數具纽麵距之_奶彡_，其㈣之鏡群皆 為三群以上，此將使得鏡⑽使料增加，造成短焦投影鏡頭 之重量與大小無法降低，而無法滿足大糊仅便攜與輕量需 求。 201219825 【發明内容】 有鑑於此，本發明之主要目的在於提供一種可變焦之短焦 投影鏡頭，是由兩組鏡群所組成，不僅體積小，且具高光學效 能。 緣以達成上述目的’本發明所提供可變焦之短焦投影鏡頭 包含有沿一光軸且由一成像侧至一像源側依序排列之一第一 鏡群與-第二鏡群；其巾’該第—鏡群具有貞屈光力，且包括 有由該成像側至該像源侧依序排列之—第—鏡片與—第二鏡 片；該第一鏡片由塑膠製成，具有負屈光力，且至少一面為非 球面表面；該第二鏡片由玻璃製成，且具有負减力；該第二 鏡群具有正屈光力；該第二鏡群由該成侧至該像源側算起最 後-片鏡片具有正屈光力’且至少—面為非球面表面；另外， 該第-鏡群可_輯顺該第二麟·該光軸移動。 藉矛J用移動該第一鏡群達到改變該短焦投影鏡頭焦距 之目的。 【實施方式】 為月b更’月楚地說明本發明，兹舉較佳實施例並配合圖示 細說明如後。 明7圖、1 ’為本發明第一較佳實施例之短焦投影鏡頭 1 /、匕3有〜光軸2：且由成像側至像源侧依序排列之一第一 201219825 鏡群G1與-第二鏡群G2。另外，依使用上的需求，在第二 鏡群G2與像源側之間更可設置-玻璃覆蓋CG (Cover Glass)，係一平板玻璃。其中： 該第-鏡群G1具有負屈光力，且包含有一第一鏡片u、 -第二鏡片L2以及-第三鏡片L3。該第一鏡片u由塑膠製 成’為一具有負屈光力之新月型透鏡，其凸面幻向成像側， 且其表面Rl、R2皆為非球面表面。該第二鏡片L2由玻璃製 成，且為一具有負屈光力之雙凹透鏡。該第三鏡片13由玻璃 製成，且為一具有正屈光力之雙凸透鏡。另外，該第一鏡群 G1可於成像側與該第二鏡群G2間，沿光軸z進行移動，以 達到改變鏡頭焦距之目的，使該短焦投影鏡頭丨可依該第一鏡 群G1之位置區分為廣角狀態、中間(此仙⑹狀態 與遠距投影(telephoto)狀態。 該第一鏡群G2具有正屈光力’且包含有由玻璃製成之一 第四鏡片L4、一第五鏡片L5、一第六鏡片L6、一第七鏡片 L7以及一第八鏡片L8。該第四鏡片L4為一具有正屈光力之 雙凸透鏡。該第五鏡片L5為一具有負屈光力之新月型透鏡， 且其凹面R9向成像側。該第六鏡片L6為一具有正屈光力之 雙凸透鏡。該第七鏡片L7為一具有負屈光力之單凹鏡片，且 其凹面R13向成像側。該第八鏡片L8為一具有正屈光力之雙 凸透鏡，且其表面R15、R16皆為非球面表面。 另外，該短焦投影鏡頭1之光圈st係位於該第六鏡片L6 201219825 與該第七鏡片L7之間。 為使該短焦投影鏡頭1能效縮減鏡頭總長，並可修正像 差，該奴紐影鏡頭1滿足下列條件： ⑴ 1.88 < lfl/叫 < 2 % ⑺ 2.9 < 陶 < 3 3 P)3.16<|fU/%|<3 83 ⑷ _〈陶 < 〇 83 其中’ Ω為辦―鏡群G1之有效焦距；β為該第二鏡群 ⑺之有效焦距；~為該短鎌影鏡頭1於廣mwide_angle) 狀態下之有效㈣…為該第—鏡以1之有效焦距；fA為 該第八鏡>i L8之有效焦距。 另外’為使軸焦投影鏡頭1能擁有較長之後焦與出瞳 (exitpupll) ’該短焦投影鏡頭1更滿足下列條件： (5) 1.12 < |ex/bf] < j 35 其中bf為該短焦投影鏡頭1之後焦長度；ex為該短焦 才又影鏡頭1之出瞳位置(exjtpUpilp〇siti〇n)。 再者，為使該短焦投影鏡頭丨能具有較佳之成像品質，該 短焦投影鏡頭1更滿足下列條件： (6) 0.035 < |n2/v2| < 0.043 其中，n2為該第二鏡片L2之折射率；V2為該第二鏡片 L2之色散係數。 本發明第一實施例之短焦投影鏡頭1的焦距F (Focus Length)、數值孔徑fn〇 (F-number)、各個鏡片表面的光軸z 通過處的曲率半徑R ( radius of curvature )、各鏡片於光軸Z上 201219825 之厚度 T (thickness)、各鏡片之折射率 Nd (refractive index) 及各鏡片之阿貝係數Vd (Abbenumber)，如表一所示··201219825 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a projection lens, and more particularly to a zoom-type short-focus projection lens. [Prior Art] With the advancement of video technology, short-focus projectors in the family space are becoming more and more popular, and they are used to clearly display the short-focus projection lens on the screen. f彡的核响件—. However, most of the short-focus projection lenses of F know that they do not have the slave of Wei, so that they can be tilted in the short-shadow movie machine, and it is impossible to adjust the image size of the projection according to the image of the mosquito screen, but the short-focus projection must be performed. Machine movement can meet the purpose of adjustment, increasing the inconvenience of users. Another aspect is the number of mirrors used in the projectors, such as φ Deviee 'DMD), (lc〇s - or LCDpand), while lifting the pixels, also towards miniaturization. Correspondingly, The short-throw projection lens has high-filament performance, _ reduce its size and weight 'to make its female looms _ compliant with the light-weight spots implanted by the silk. And a few with a noodle distance _ milk 彡 _, its (4) The mirror group is more than three groups, which will increase the size of the mirror (10), which will make the weight and size of the short-focus projection lens not be reduced, and can not meet the demand for large paste only portable and lightweight. 201219825 [Inventive content] Therefore, the main object of the present invention is to provide a zoomable short-focus projection lens, which is composed of two groups of mirrors, which is not only small in size but also has high optical performance. In order to achieve the above object, the zoom lens provided by the present invention is provided. The short-focus projection lens comprises a first mirror group and a second mirror group arranged along an optical axis and arranged from an imaging side to an image source side; the towel group has a pupil refractive power and includes There is a side from the imaging side to the image source side Arranging the first lens and the second lens; the first lens is made of plastic, has a negative refractive power, and at least one side is an aspherical surface; the second lens is made of glass and has a negative force reduction; The second mirror group has a positive refractive power; the second mirror group has a positive refractive power from the side to the image source side and the at least one surface is an aspherical surface; in addition, the first mirror group can be _ The optical axis moves by the second lining. The purpose of changing the focal length of the short focal projection lens is to move the first mirror group by using the spear J. [Embodiment] The present invention is described for the month b. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following is a detailed description of the following: FIG. 7 and FIG. 1 are a short-focus projection lens 1 /, 匕 3 having an optical axis 2 of the first preferred embodiment of the present invention: and from the imaging side to One of the first 201219825 mirror group G1 and the second mirror group G2 are arranged in sequence like the source side. In addition, depending on the requirements of use, a glass cover CG can be set between the second mirror group G2 and the image source side ( Cover Glass), which is a flat glass, wherein: the first mirror group G1 has a negative refractive power and includes a first lens u, a second lens L2, and a third lens L3. The first lens u is made of plastic as a crescent lens having a negative refractive power, the convex side of which is convex toward the imaging side, and the surface Rl, R2 is an aspherical surface. The second lens L2 is made of glass and is a biconcave lens having a negative refractive power. The third lens 13 is made of glass and is a lenticular lens having positive refractive power. The first mirror group G1 can be moved along the optical axis z between the imaging side and the second mirror group G2 to achieve the purpose of changing the focal length of the lens, so that the short focal projection lens can be positioned according to the first mirror group G1. It is divided into a wide-angle state, a middle (this fairy (6) state and a telephoto state. The first mirror group G2 has a positive refractive power ' and includes a fourth lens L4 made of glass, a fifth lens L5, A sixth lens L6, a seventh lens L7 and an eighth lens L8. The fourth lens L4 is a lenticular lens having a positive refractive power. The fifth lens L5 is a crescent lens having a negative refractive power, and its concave surface R9 is directed to the imaging side. The sixth lens L6 is a lenticular lens having a positive refractive power. The seventh lens L7 is a single concave lens having a negative refractive power, and its concave surface R13 is directed to the imaging side. The eighth lens L8 is a lenticular lens having a positive refractive power, and the surfaces R15 and R16 are aspherical surfaces. In addition, the aperture st of the short-focus projection lens 1 is located between the sixth lens L6 201219825 and the seventh lens L7. In order to make the short-focus projection lens 1 reduce the total length of the lens and correct the aberration, the slave shadow lens 1 satisfies the following conditions: (1) 1.88 < lfl/called < 2 % (7) 2.9 < Tao < 3 3 P ) 3.16<|fU/%|<3 83 (4) _<陶< 〇83 where ' Ω is the effective focal length of the mirror group G1; β is the effective focal length of the second mirror group (7); The photographic lens 1 is effective in the wide mwide_angle state (four) ... is the effective focal length of the first mirror; fA is the effective focal length of the eighth mirror > i L8. In addition, in order to make the axial projection lens 1 have a longer post-focus and exitpupll, the short-focus projection lens 1 satisfies the following conditions: (5) 1.12 < |ex/bf] < j 35 where bf For this short-focus projection lens 1 after the focal length; ex is the short focus to reproduce the exit position of the lens 1 (exjtpUpilp〇siti〇n). Furthermore, in order to enable the short-focus projection lens to have better image quality, the short-focus projection lens 1 satisfies the following conditions: (6) 0.035 < |n2/v2| < 0.043 wherein n2 is the second The refractive index of the lens L2; V2 is the dispersion coefficient of the second lens L2. The focal length F (Focus Length), the numerical aperture fn 〇 (F-number) of the short-focus projection lens 1 of the first embodiment of the present invention, and the radius of curvature R of the optical axis z of each lens surface, The thickness T of the lens on the optical axis Z of 201219825, the refractive index of each lens Nd (refractive index) and the Abbe number of each lens (Abbenumber) are shown in Table 1.
表一 —F=1C • 1859(W)~11.1948(M)~12.1718(T) FN0=2. 578(W)~2. 678(M)~2. 777(T) 表面 R(mm) T(mm) Nd Vd 備註 _J1 59.61 3.57 1.525 56.40 第一鏡片LI —R2 12.94 15.13 R3 -46. 24 1.5 1.788 47. 37 第一鏡片L2 R4 31.36 6.488 一~ R5 71.80 5.51 1.834 37.16 第三鏡片L3 R6 -62. 59 27. 641(W)~20. 632(M)-14. 953(T) R7 24.51 5.31 1.532 48. 84 _第四鏡片L4 R8 -133.41 13.56 R9 -17.63 0. 60 1.805 25.43 第五鏡片L5 R10 -102.88 0.10 K11 Π 15.12 2.81 1.497 81.55 第六鏡片L6 R12 -27. 46 3. 03 ST Infinity 2. 93 光圈 R13 -25. 85 4.32 1.835 42. 71 第七鏡片L7 R14 Infinity 0.10 R15 39. 31 2^34 ~ 1.690 52.76 第八鏡片L8 __R16 -30. 39 20.0 R17 Infinity 1.05 1.488 70.24 玻璃覆蓋CG [Tl8 Infinity 1. 950(W)~3.128(M)~4. 278⑺ 表一之厚度T中，（W)是指該短焦投影鏡頭1在廣角 (wide-angle)狀態時，於光轴Z上之間距；（μ)是指該短焦投影 鏡頭1在中間(middle)狀態時，於光軸z上之間距；（τ)是指該 短焦投影鏡頭1在長距投影(telephoto)狀態時，於光轴ζ上之 間距。 另外，本實施例中之該等非球面表面R1、幻、R15及R16 之表面凹陷度D由下列公式所得到： 201219825 C , 2 +uw + En·^'2 +Eu.H14 +El6-H'6Table 1—F=1C • 1859(W)~11.1948(M)~12.1718(T) FN0=2. 578(W)~2. 678(M)~2. 777(T) Surface R(mm) T( Mm) Nd Vd Remarks _J1 59.61 3.57 1.525 56.40 First lens LI — R2 12.94 15.13 R3 -46. 24 1.5 1.788 47. 37 First lens L2 R4 31.36 6.488 One ~ R5 71.80 5.51 1.834 37.16 Third lens L3 R6 -62 59 27. 641(W)~20. 632(M)-14.953(T) R7 24.51 5.31 1.532 48. 84 _Fourth lens L4 R8 -133.41 13.56 R9 -17.63 0. 60 1.805 25.43 Fifth lens L5 R10 -102.88 0.10 K11 Π 15.12 2.81 1.497 81.55 Sixth lens L6 R12 -27. 46 3. 03 ST Infinity 2. 93 Aperture R13 -25. 85 4.32 1.835 42. 71 Seventh lens L7 R14 Infinity 0.10 R15 39. 31 2 ^34 ~ 1.690 52.76 Eighth L8 __R16 -30. 39 20.0 R17 Infinity 1.05 1.488 70.24 Glass Covered CG [Tl8 Infinity 1. 950(W)~3.128(M)~4. 278(7) Table 1 thickness T, (W ) refers to the distance between the short-focus projection lens 1 on the optical axis Z in the wide-angle state; (μ) refers to the short-focus projection lens 1 in the middle state, on the optical axis z Upper distance ([Tau]) refers to the short focal length projection lens 1 when the projection distance (a telephoto) state, the distance on the optical axis ζ. In addition, the surface depression D of the aspherical surfaces R1, 幻, R15, and R16 in the present embodiment is obtained by the following formula: 201219825 C , 2 +uw + En·^'2 +Eu.H14 +El6-H '6
l；7l - (l"+ /cRTF +E^H'+Ee^6^Es.H 其中： D:非球面表面之凹陷度； C:曲率半徑之倒數； Η:表面之孔徑半徑； Κ:圓錐係數； Ε4〜Ε16 :表面之孔徑半徑Η的各階係數。 在本實施例中，各個非球面表面的圓錐係數K (conic constant)及表面孔徑半徑η的各階係數E4〜m6如表二所示： 表二l;7l - (l"+ /cRTF +E^H'+Ee^6^Es.H where: D: the aspherical surface of the depression; C: the reciprocal of the radius of curvature; Η: the aperture radius of the surface; Cone coefficient; Ε4~Ε16: various order coefficients of the aperture radius Η of the surface. In this embodiment, the conic coefficients K (conic constant) of each aspheric surface and the order coefficients E4 to m6 of the surface aperture radius η are as shown in Table 2. : Table II
藉由上述的鏡片與光圈之配置，使得本實施例之短焦投影 鏡頭1不但可有效縮小體積以滿足輕量化之需求，該短焦投影 鏡頭1在廣角(wide-angle)狀態時，其成像品質上也可達到要 求’這可從圖2A至圖2D看出。 圖2A所示的’是本實施例之短焦投影鏡頭1的縱向色差 圖；圖2B所示的，是本實施例之短焦投影鏡頭1的橫向色差 圖；圖2C所示的’是本實施例之短焦投影鏡頭1的場曲圖及 畸變圖；圖2D所示的，是本實施例之短焦投影鏡頭1的空間 201219825 頻率調制傳遞函數圖（Spatial 從圖2a及圖 2B可看丨，本實細織投f彡綱丨之縱向色差最大不超過 〇.〇6mm和-0.02mm，橫向色差最大不超過_和加。從圖 2C可看出，本實施例短焦投影鏡頭丨之最大場曲不超過 0.10mm與-〇.i0mm，且畸變量不超過2%。從圖21)可看出， 本實施例短焦投影鏡頭1在80 lp/mm的時候，其調制光學傳 遞函數值仍維持在40%以上。 另外，該短焦投影鏡頭1在中間(middle)狀態時，其成像 品質上也可達到要求，這可從圖3A至圖3d看出。從圖3a 及圖3B可看出，本實施例短焦投影鏡頭丨之縱向色差最大不 超過0.06mm和-0.01mm ’橫向色差最大不超過5μιη和_丨哗。 從圖3 C可看出，本實施例短焦投影鏡頭丨之最大場曲不超過 0.10mm與-〇.l〇mm，且畸變量不超過1%。從圖3d可看出， 本實施例短焦投影鏡頭1在8〇 ip/mm的時候，其調制光學傳 遞函數值仍維持在40%以上。 再者，該短焦投影鏡頭1在長距投影(teleph〇t〇)狀態時， 其成像品質上也可達到要求，這可從圖4A至圖4D看出。從 圖4A及圖4B可看出，本實施例短焦投影鏡頭〗之縱向色差 最大不超過0.08mm和-〇.〇lmm，橫向色差最大不超過5μιη和 -2μπι。從圖4C可看出，本實施例短焦投影鏡頭丨之最大場曲 不超過0.10mm與-0.10mm ’且畸變量不超過1%。從圖4D可 看出，本實施例短焦投影鏡頭1在80 lp/mm的時候，其調制 201219825 光學傳遞函數值仍維持在2〇%以上，顯見本實施例之短焦投影 鏡頭1的解析度不管是在是廣角⑽如-肪咏)狀態、中間(middle) 狀態或是長距投影(telephoto)狀態時，都是符合標準的。 以上所述的，是本發明第一實施例的短焦投影鏡頭1 ;依 據本發明的技術，以下配合圖5說明本發明的第二實施例。 本實施例之短焦投影鏡頭2包含有沿光轴Z且由成像側至 像源側依序排列設置之一第一鏡群G1與一第二鏡群〇2。另 外，在該第二鏡群G2與像源侧之間同樣設置有一玻璃覆蓋 CG。 該第一鏡群G1具有負屈光力，且包含有一第一鏡片L1、 一第二鏡片L2以及一第三鏡片L3。該第一鏡片L1由塑膠製 成’為一具有負屈光力之新月型透鏡，其R1凸面向成像侧’ 且其表面IU、R2皆為非球面表面。該第二鏡片L2由玻璃製 成，且為一具有負屈光力之雙凹透鏡。該第三鏡片L3由玻璃 製成，且為一具有正屈光力之雙凸透鏡。另外，該第一鏡群 G1可於成像側與該第二鏡群G2間，沿光軸Z進行移動，以 達到改變鏡頭焦距之目的，使該短焦投影鏡頭2可依該第一鏡 群G1之位置區分為廣角(wide-angle)狀態、中間(middle)狀態 與遠距投影(telephoto)狀態。 該第一鏡群G2具有正屈光力’且包含有由玻璃製成之一 第四鏡片L4、一第五鏡片L5、一第六鏡片L6以及一第七鏡 201219825 片L7。該第四鏡片L4為一具有正屈光力之雙凸透鏡。該第五 鏡片L5為一具有正屈光力之雙凸透鏡。該第六鏡片l6為一 具有負屈光力之單凹鏡片，且其凹面RU向成像侧。該第七鏡 片L7為一具有正屈光力之雙凸透鏡，且其表面R13、R14皆 為非球面表面。 另外，該短焦投影鏡頭2之光圈ST係位於該第六鏡片L6 之表面R12上。 為使該短焦投影鏡頭2能效縮減鏡頭總長，並修正像差， 且可《b擁有較長之後焦與出瞳(exit pupil)，以及具有較佳之成 像品質，該短焦投影鏡頭2滿足下列條件： ⑴ 1.88 < 陶 < 2.58 (2) 2.9 < 陶 < 3·3 (3)3.16<|fLl/fsv|<3.83 (4) 0.64 < |fA7f2| < 0.83 (5) 1.12 < lex/bf! < L35 ⑹ 0.035 < |n2/v2| < α〇43 其中’ Ω為該第—麟G1之有效焦距；£2為該第二鏡群 G2之有效焦距；&為該短焦投影鏡頭2於廣肖(wid議㈣ 狀態下之有效焦距；似為該第一鏡片u之有效焦距；仏為 該第七鏡4 L7之有效焦距；bf為驗焦辦彡麵2之後焦長 度A為該短焦投影鏡頭2之出曈位置㈣咖喊㈣；以 為該第二鏡片L2之折射率；v2為該第二鏡片u之色散係數。 本發明第二實施例之短焦投影鏡頭2的焦距F (f_ Length)、數值孔徑FN〇 (F_numbe〇、各個鏡片表面的光轴z 通過處的曲率半徑R ( radius Qf贿敵）、各鏡片於光轴Z上 201219825 之厚度 Τ (thickness )、各鏡片之折射率 Nd ( refractive index ) 及各鏡片之阿貝係數Vd (Abbenumber)，如表三所示：With the above arrangement of the lens and the aperture, the short-focus projection lens 1 of the present embodiment can effectively reduce the volume to meet the demand for light weight, and the short-focus projection lens 1 is imaged in a wide-angle state. The quality can also meet the requirements'. This can be seen from Figure 2A to Figure 2D. 2A is a longitudinal chromatic aberration diagram of the short-focus projection lens 1 of the present embodiment; FIG. 2B is a lateral chromatic aberration diagram of the short-focus projection lens 1 of the present embodiment; and FIG. 2C is 'this is The field curvature diagram and the distortion diagram of the short-focus projection lens 1 of the embodiment; FIG. 2D shows the space modulation transfer function diagram of the space 201219825 of the short-focus projection lens 1 of the present embodiment (Spatial can be seen from FIG. 2a and FIG. 2B)丨, the longitudinal chromatic aberration of the actual fine weave is not more than 〇.〇6mm and -0.02mm, and the lateral chromatic aberration is not more than _ and plus. As can be seen from Fig. 2C, the short-focus projection lens of this embodiment丨The maximum field curvature is no more than 0.10mm and -〇.i0mm, and the distortion variable does not exceed 2%. As can be seen from Fig. 21), the short-focus projection lens 1 of this embodiment has a modulation optical transmission at 80 lp/mm. The function value is still maintained above 40%. In addition, the short-focus projection lens 1 can also meet the imaging quality in the middle state, which can be seen from Figs. 3A to 3d. As can be seen from Fig. 3a and Fig. 3B, the longitudinal chromatic aberration of the short-focus projection lens of the present embodiment does not exceed 0.06 mm and -0.01 mm ′ at the maximum, and the lateral chromatic aberration does not exceed 5 μm and _丨哗 at the maximum. As can be seen from Fig. 3C, the maximum field curvature of the short-focus projection lens of this embodiment does not exceed 0.10 mm and -〇.l〇mm, and the distortion variable does not exceed 1%. As can be seen from Fig. 3d, the value of the modulation optical transfer function of the short-throw projection lens 1 of this embodiment is maintained at 40% or more at 8 〇 ip/mm. Furthermore, the short-focus projection lens 1 can also meet the imaging quality in the long-distance projection (teleph〇t〇) state, which can be seen from FIG. 4A to FIG. 4D. As can be seen from Figs. 4A and 4B, the longitudinal chromatic aberration of the short-throw projection lens of the present embodiment is not more than 0.08 mm and - 〇. 〇 lmm, and the lateral chromatic aberration is not more than 5 μm and -2 μm. As can be seen from Fig. 4C, the maximum field curvature of the short-throw projection lens of this embodiment does not exceed 0.10 mm and -0.10 mm' and the distortion variable does not exceed 1%. As can be seen from FIG. 4D, when the short-focus projection lens 1 of the present embodiment is at 80 lp/mm, the optical transmission function value of the modulation 201219825 is maintained at 2% or more, and the analysis of the short-focus projection lens 1 of the present embodiment is apparent. Whether it is in the wide-angle (10), such as - fat state, middle state or telephoto state, it is standard. The above is the short-focus projection lens 1 of the first embodiment of the present invention; according to the technology of the present invention, a second embodiment of the present invention will be described below with reference to FIG. The short-focus projection lens 2 of the present embodiment includes a first mirror group G1 and a second mirror group 沿2 arranged along the optical axis Z and arranged in order from the imaging side to the image source side. Further, a glass cover CG is also provided between the second mirror group G2 and the image source side. The first mirror group G1 has a negative refractive power and includes a first lens L1, a second lens L2, and a third lens L3. The first lens L1 is made of plastic and is a crescent lens having a negative refractive power, the R1 convex surface facing the image forming side and the surfaces IU and R2 of which are aspherical surfaces. The second lens L2 is made of glass and is a biconcave lens having a negative refractive power. The third lens L3 is made of glass and is a lenticular lens having positive refractive power. In addition, the first mirror group G1 can be moved along the optical axis Z between the imaging side and the second mirror group G2 to achieve the purpose of changing the focal length of the lens, so that the short-focus projection lens 2 can be according to the first mirror group. The position of G1 is divided into a wide-angle state, a middle state, and a telephoto state. The first mirror group G2 has a positive refractive power and includes a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh mirror 201219825 sheet L7 made of glass. The fourth lens L4 is a lenticular lens having a positive refractive power. The fifth lens L5 is a lenticular lens having a positive refractive power. The sixth lens 16 is a single concave lens having a negative refractive power, and its concave surface RU faces the image forming side. The seventh lens L7 is a lenticular lens having positive refractive power, and the surfaces R13 and R14 are aspherical surfaces. Further, the aperture ST of the short-focus projection lens 2 is located on the surface R12 of the sixth lens L6. In order to make the short-focus projection lens 2 reduce the total length of the lens and correct the aberration, and "b has a longer post focus and exit pupil, and has better imaging quality, the short-focus projection lens 2 satisfies the following Conditions: (1) 1.88 <Tao< 2.58 (2) 2.9 <Tao<3·3(3)3.16<|fLl/fsv|<3.83 (4) 0.64 < |fA7f2| < 0.83 (5 1.12 < lex/bf! < L35 (6) 0.035 < |n2/v2| < α〇43 where ' Ω is the effective focal length of the first-lin G1; £2 is the effective focal length of the second mirror group G2 ; & is the effective focal length of the short-focus projection lens 2 in the state of Wid (four); it seems to be the effective focal length of the first lens u; 仏 is the effective focal length of the seventh mirror 4 L7; bf is the focal length After the facet 2, the focal length A is the exit position of the short-focus projection lens 2 (4) the coffee call (4); the refractive index of the second lens L2; v2 is the dispersion coefficient of the second lens u. The second embodiment of the present invention For example, the focal length F (f_Length) of the short-focus projection lens 2, the numerical aperture FN〇 (F_numbe〇, the radius of curvature R of the optical axis z of each lens surface, (radius Qf), each mirror Thickness Τ (thickness) on the optical axis Z 201219825, the refractive index of each lens of Nd (refractive index) and each lens of the Abbe's number Vd (Abbenumber), as shown in Table 3:
F=10 1611(ff)~ll. Q756(M)~12.1786(T)_FN0=2 550(W)~2. 653(M)~2. 780(T) 表面 R(mm) T(mm) Nd Vd 備註 R1 199.22 6. 48 1.525 56.40 第一鏡片LI R2 18.38 21.36 R3 -36. 52 0.80 1.835 42.71 第一鏡片L2 R4 30.50 4. 354(W)-4. 634(M)~4. 903(T) R5 55. 62 6.27 1.673 32.10 第=鏡片L3 R6 -52. 38 11.58(W)~5. 928(M)~0. l〇(T) R7 149. 03 2. 98 1.654 39.68 第四鏡片L4 R8 -105.55 22.86 R9 17.57 3.79 1.497 81.55 第五鏡片L5 RIO -134.94 7.59 Rll -22. 91 4.81 1.847 23.78 第六鏡片L6 R12 Infinity 0.90 光圈ST R13 49.10 4.30 1.484 70.26 第七鏡片L7 R14 -15. 35 21.0 R15 Infinity 1.05 1.507 63.13 玻璃覆蓋CG R16 Infinity 3. 380(W)~4. 599(M)~6. 094(T) 表三之厚度T中’（w)是指該短焦投影鏡頭2在廣角 (wide-angle)狀態時’於光軸Z上之間距；（Μ)是指該短焦投影 鏡頭2在中間(middle)狀態時’於光軸ζ上之間距；⑺是指該 短焦投影鏡頭2在長距投影(telephoto)狀態時，於光轴Z上之 間距。 另外’本實施例中之該等非球面表面幻、们、幻3及R14 之表面凹陷度D由下列公式所得到： 〇 = ~φ-(ΐ + κ).^.Η^ +Ε^Η4+Ε6-Η6+Ε^Ηί^ι〇.Η-+Εη.Η-+ΕΗ·Η-+Ε16.Η- 其中： 201219825 D:非球面表面之凹陷度； C:曲率半徑之倒數； Η:表面之孔徑半徑； Κ:圓錐係數； Ε4〜Ε16 :表面之孔徑半徑Η的各階係數。 在本實施例中’各個非球面表面的圓錐係數K (conic constant)及表面孔徑半徑Η的各階係數E4〜E16如表四所示： 表四 表面 Κ Ε4 Ε6 Ε8 Ε10 Ε12 Ε14 Ε16 R1 -163.558 1.91Ε-05 -2. 84Ε-08 2. 22Ε-11 1.40Ε-15 -1.45Ε-17 9. 05Ε-21 -1. 56Ε-24 R2 -0. 25962 1.60Ε-05 -2. 74Ε-08 2.18Ε-10 -1.62Ε-12 1.99Ε-15 6. 62Ε-18 -1.62Ε-20 R13 0 -0. 0001 -4.44Ε-07 -1.44Ε-09 -2.03Ε-10 0 0 0 R14 0 3. 87Ε-06 -7.16Ε-07 7. 50Ε-09 -2. 22Ε-10 0 0 0 藉由上述的鏡片與光圈之配置，使得本實施例之短焦投影 鏡頭2不但可有效縮小體積以滿足輕量化之需求，該短焦投影 鏡頭2在廣角(wide-angle)狀態時，其成像品質上也可達到要 求，這可從圖6A至圖6D看出。 圖6A所示的’疋本實施例之短焦投影鏡頭2的縱向色差 圖；圖6B所示的，是本實施例之短焦投影鏡頭2的橫向色差 圖；圖6C所示的’是本實施例之短焦投影鏡頭2的場曲圖及 畸變圖；圖6D所示的’是本實施例之短焦投影鏡頭2的空間 頻率調制傳遞函數圖（Spatial Frequency MTF )。從圖6 A及圖 6B可看出，本實施例短焦投影鏡頭2之縱向色差最大不超過 13 201219825 0.04mm和-0.04mm，橫向色差最大不超過5μηι和-Ιμιη。從圖 6 C可看出，本實施例短焦投影鏡頭2之最大場曲不超過 0.10mm與-0.10mm，且畸變量不超過2%。從圖6 D可看出， 本實施例短焦投影鏡頭2在80 lp/mm的時候’其調制光學傳 遞函數值仍維持在50%以上。 另外，該短焦投影鏡頭2在中間(middle)狀態時，其成像 品質上也可達到要求，這可從圖7A至圖7D看出。從圖7A 及圖7B可看出’本實施例短焦投影鏡頭2之縱向色差最大不 超過0.05mm和-0.05mm ’橫向色差最大不超過5μιη *_1μιη。 從圖7C可看出，本實施例短焦投影鏡頭2之最大場曲不超過 〇.〇5mm與-〇.l〇mm，且畸變量不超過1%。從圖可看出， 本實施例短焦投影鏡頭2在80 lp/mm的時候，其調制光學傳 遞函數值仍維持在50%以上。 再者，該短焦投影鏡頭2在長距投影(teieph〇to)狀態時， 其成像品質上也可達到要求，這可從圖8A至圖8D看出。從 圖8A及圖8B可看出，本實施例短焦投影鏡頭2之縱向色差 最大不超過a〇6mm和_0.06mm，橫向色差最大不超過5μιη和 3师°從圖8 C可看出’本實施例短焦投影鏡頭2之最大場曲 不超過0.1〇mm與_0 1〇mm，且畸變量不超過2%。從圖8d可 看出本實施例短焦投影鏡頭2在80 lp/mm的時候，其調制 光予傳遞函數值仍維持在5〇%以上。藉此，顯見本實施例之短 …、又5V鏡頭2的解析度不管是在是廣角(碰e_angie)狀態、中間 201219825 (middle)狀態或是長距投影(teleph〇t〇)狀態時，都是符合標準 的。 請參閱圖9 ’為本發明第三較佳實施例短焦投影鏡頭3之 鏡片配置圖’其包含有沿光軸z且由成像侧至像源侧依序排列 設置之一第一鏡群G1與一第二鏡群G2。另外，在該第二鏡 群G2與像源側間同樣設有一玻璃覆蓋。其中： 該第一鏡群G1具有負屈光力，且包含有一第一鏡片u、 一第二鏡片L2以及一第三鏡片l3。該第一鏡片u由塑膠製 成，為一具有負屈光力之新月型透鏡，其凸面尺丨向成像侧， 且其表面Rl、R2皆為非球面表面。該第二鏡片[2由玻璃製 成’且為一具有負屈光力之雙凹透鏡。該第三鏡片L3由玻璃 製成，且為一具有正屈光力之雙凸透鏡。另外，該第一鏡群 G1可於成像側與該第二鏡群G2間，沿光軸z進行移動，以 達到改變鏡頭焦距之目的’使該短焦投影鏡頭3可依該第一鏡 群G1之位置區分為廣角㈣如观咏)狀態、中間(middle)狀態 與遠距投影(telephoto)狀態。 該第一鏡群G2具有正屈光力，且包含有由玻璃製成之一 第四鏡片L4、一第五鏡片L5、一第六鏡片L6以及一第七鏡 片L7。該第四鏡片L4為一具有正屈光力之雙凸透鏡。該第五 鏡片L5為一具有正屈光力之雙凸透鏡。該第六鏡片L6為一 具有負屈光力之膠合透鏡’係由一新月型透鏡L61與一雙凹透 鏡L62焦合而成；該新月型透鏡L6]l之凹面R11向成像侧， 15 201219825 且較該雙凹透鏡L62接近成像侧。該第七鏡片為一具有正 屈光力之雙凸透鏡，且其表面R14、R15皆為非球面表面。 另外，該短焦投影鏡頭3之光圈ST係位於該第七鏡片L7 之表面R14上。 為使該短焦投影鏡頭3能效縮減鏡頭總長，並修正像差， 且可肖b擁有較長之後焦與出瞳(exit pUpii)，以及具有較佳之成 像品質’該短焦投影鏡頭3滿足下列條件： (1) 1.88 <|fl/fw|< 2.58 (2) 2.9 < |f2/fw| < 3.3 (3) 3.16 < |fLl/fw| < 3.83 (4) 0.64 < |fA7f2| < 0.83 (5) 1.12<|e^f] < 135 ⑹ 0.035 < |n2/v2| < 0.043 其中，Π為該第一鏡群G1之有效焦距；f2為該第二鏡群 G2之有效焦距；加為該短焦投影鏡頭3於廣角㈣de angle) 狀態下之有效焦距；fLl為該第一鏡片L1之有效焦距；伙為 該第七鏡片L7之有效焦距；bf為該短焦投影鏡頭3之後焦長 度’ ex為該短焦投影鏡頭3之出曈位置(exit pupil position); n2 為該第二鏡片L2之折射率；ν2為該第二鏡片L2之色散係數。 本發明第二實施例之短焦投影鏡頭3的焦距F ( Focus Length)、數值孔徑fn〇 (F-number)、各個鏡片表面的光軸z 通過處的曲率半徑R ( radius of curvature )、各鏡片於光軸Z上 之厚度 T (thickness)、各鏡片之折射率 Nd (refractive index) 及各鏡片之阿貝係數Vd (Abbe number)，如表五所示： 201219825 F=10.1525(W)~11.0671(M)~12.1688(T)__FN0=2. 550(W)~2. 660(M)~2. 792(T) 表面 R(mm) T(mm) Nd Vd 備註 R1 170.40 6.50 1.525 56.40 第一鏡片Ll_ R2 17.70 19.15 R3 -41.13 0.80 1.804 46. 57 第二鏡片L2 一R4 27.0 6.0(W)~6.415(M)~6.811(T) R5 57.40 6.47 1.648 33.79 第三鏡片L3 R6 -64. 20 17. 536(W)~11.882(M)~6. 035(T) R7 65.50 6.50 1.729 54. 68 第四鏡片L4 R8 -200.80 16.0 R9 18.38 4.49 1.497 81.55 第五鏡片L5— R10 -132.40 5. 80 R11 -65.17 2. 07 1.516 64.14 第六鏡片L6 R12 -12.94 0.80 1.834 37.16 —1 R13 50.30 2. 07 - R14 45.83 4.79 1.495 81.04 第七鏡片L7 光圈ST R15 -13.41 21.0 R16 Infinity 1.05 1.507 63.13 玻璃覆蓋 R17 Infinity 3.411(W)~4. 663(M)~6.197(T) 表五之厚度T中，（W)是指該短焦投影鏡頭3在廣角 (wide-angle)狀態時，於光轴Z上之間距；（Μ)是指該短焦投影 鏡頭3在中間(middle)狀態時，於光轴Ζ上之間距；（Τ)是指該 短焦投影鏡頭3在長距投影(telephoto)狀態時，於光軸Z上之 間距。 另外’本實施例中之該等非球面表面幻、R2、R14及r15 之表面凹陷度D由下列公式所得到： C-H2 ^ + 1T^TkJ=^=^ + E^HA +E6'H6+E^Ht +E^〇-Hl° +Εη·^'2 +Ε^·Η'Α +Ε16·Η16 其中： D:非球面表面之凹陷度； C:曲率半徑之倒數； 17 201219825 Η:表面之孔徑半徑； Κ =圓錐係數； Ε4〜Ε16 :表面之孔徑半徑η的各階係數。 在本實施例中，各個非球面表面的圓錐係數K (conic constant)及表面孔徑半徑η的各階係數£4〜腿如表六所示： 表六F=10 1611(ff)~ll. Q756(M)~12.1786(T)_FN0=2 550(W)~2. 653(M)~2. 780(T) Surface R(mm) T(mm) Nd Vd Remarks R1 199.22 6. 48 1.525 56.40 First lens LI R2 18.38 21.36 R3 -36. 52 0.80 1.835 42.71 First lens L2 R4 30.50 4. 354(W)-4. 634(M)~4. 903(T) R5 55. 62 6.27 1.673 32.10 The second lens L3 R6 -52. 38 11.58(W)~5. 928(M)~0. l〇(T) R7 149. 03 2. 98 1.654 39.68 Fourth lens L4 R8 - 105.55 22.86 R9 17.57 3.79 1.497 81.55 Fifth lens L5 RIO -134.94 7.59 Rll -22. 91 4.81 1.847 23.78 Sixth lens L6 R12 Infinity 0.90 Aperture ST R13 49.10 4.30 1.484 70.26 Seventh lens L7 R14 -15. 35 21.0 R15 Infinity 1.05 1.507 63.13 Glass Covered CG R16 Infinity 3. 380(W)~4. 599(M)~6. 094(T) The thickness T of Table 3 '(w) means that the short throw projection lens 2 is at wide angle (wide- Angle) is the distance between the optical axis Z; (Μ) refers to the distance between the short-throw projection lens 2 in the middle state on the optical axis ;; (7) means that the short-focus projection lens 2 is In the telephoto state, the distance is on the optical axis Z. In addition, the surface depression degree D of the aspherical surface, the illusion 3 and the R14 in the present embodiment is obtained by the following formula: 〇 = ~φ-(ΐ + κ).^.Η^ +Ε^Η4 +Ε6-Η6+Ε^Ηί^ι〇.Η-+Εη.Η-+ΕΗ·Η-+Ε16.Η- where: 201219825 D: the aspheric surface of the depression; C: the reciprocal of the radius of curvature; Aperture radius of the surface; Κ: conic coefficient; Ε4~Ε16: various order coefficients of the aperture radius Η of the surface. In the present embodiment, the conic coefficients K and the surface aperture radius 各个 of the respective aspherical surfaces are as shown in Table 4: Table 4 Surface Κ Ε4 Ε6 Ε8 Ε10 Ε12 Ε14 Ε16 R1 -163.558 1.91 Ε-05 -2. 84Ε-08 2. 22Ε-11 1.40Ε-15 -1.45Ε-17 9. 05Ε-21 -1. 56Ε-24 R2 -0. 25962 1.60Ε-05 -2. 74Ε-08 2.18 Ε-10 -1.62Ε-12 1.99Ε-15 6. 62Ε-18 -1.62Ε-20 R13 0 -0. 0001 -4.44Ε-07 -1.44Ε-09 -2.03Ε-10 0 0 0 R14 0 3. 87Ε-06 -7.16Ε-07 7. 50Ε-09 -2. 22Ε-10 0 0 0 By the above configuration of the lens and the aperture, the short-focus projection lens 2 of the present embodiment can effectively reduce the volume to meet the light weight. To quantify the demand, the short-focus projection lens 2 can also meet the imaging quality in the wide-angle state, which can be seen from FIG. 6A to FIG. 6D. FIG. 6A is a longitudinal chromatic aberration diagram of the short-focus projection lens 2 of the present embodiment; FIG. 6B is a lateral chromatic aberration diagram of the short-focus projection lens 2 of the present embodiment; The field curvature diagram and the distortion diagram of the short-focus projection lens 2 of the embodiment; FIG. 6D is the spatial frequency modulation transfer function diagram (Spatial Frequency MTF) of the short-focus projection lens 2 of the present embodiment. As can be seen from FIG. 6A and FIG. 6B, the longitudinal chromatic aberration of the short-focus projection lens 2 of the present embodiment does not exceed 13 201219825 0.04 mm and -0.04 mm, and the lateral chromatic aberration does not exceed 5 μm and -Ιμιη at the maximum. As can be seen from Fig. 6C, the maximum field curvature of the short-focus projection lens 2 of the present embodiment does not exceed 0.10 mm and -0.10 mm, and the distortion variable does not exceed 2%. As can be seen from Fig. 6D, the short-throw projection lens 2 of the present embodiment maintains the value of the modulation optical transfer function at 50% or more at 80 lp/mm. In addition, the short-focus projection lens 2 can also meet the imaging quality in the middle state, which can be seen from Figs. 7A to 7D. As can be seen from Figs. 7A and 7B, the longitudinal chromatic aberration of the short-throw projection lens 2 of the present embodiment is not more than 0.05 mm and -0.05 mm ′ at the maximum, and the lateral chromatic aberration is not more than 5 μm × 1 μm. As can be seen from Fig. 7C, the maximum field curvature of the short-focus projection lens 2 of the present embodiment does not exceed 〇.〇5 mm and -〇.l〇mm, and the distortion variable does not exceed 1%. As can be seen from the figure, the value of the modulation optical transfer function of the short-throw projection lens 2 of this embodiment is maintained at 50% or more at 80 lp/mm. Furthermore, the short-focus projection lens 2 can also meet the imaging quality in the long-distance projection state, which can be seen from FIG. 8A to FIG. 8D. As can be seen from FIG. 8A and FIG. 8B, the longitudinal chromatic aberration of the short-focus projection lens 2 of the present embodiment does not exceed a〇6 mm and _0.06 mm at the maximum, and the lateral chromatic aberration does not exceed 5 μm at the maximum and 3 divisions can be seen from FIG. 8C. In this embodiment, the maximum field curvature of the short-focus projection lens 2 does not exceed 0.1 〇 mm and _0 1 〇 mm, and the distortion variable does not exceed 2%. It can be seen from Fig. 8d that the short-focus projection lens 2 of the present embodiment maintains the modulation light transfer function value at more than 5% when the temperature is 80 lp/mm. Therefore, it is obvious that the resolution of the fifth embodiment and the 5V lens 2 are both in the wide-angle (e_angie) state, the middle 201219825 (middle) state, or the long-distance projection (teleph〇t〇) state. Is in line with the standard. 9 is a lens configuration diagram of a short-focus projection lens 3 according to a third preferred embodiment of the present invention, which includes a first mirror group G1 arranged along the optical axis z and sequentially arranged from the imaging side to the image source side. With a second mirror group G2. Further, a glass cover is provided between the second mirror group G2 and the image source side. Wherein: the first mirror group G1 has a negative refractive power and includes a first lens u, a second lens L2 and a third lens l3. The first lens u is made of plastic and is a crescent lens having a negative refractive power, the convex surface of which is convex toward the imaging side, and the surfaces R1 and R2 thereof are all aspherical surfaces. The second lens [2 is made of glass] and is a biconcave lens having a negative refractive power. The third lens L3 is made of glass and is a lenticular lens having positive refractive power. In addition, the first mirror group G1 can be moved along the optical axis z between the imaging side and the second mirror group G2 to achieve the purpose of changing the focal length of the lens, so that the short-focus projection lens 3 can be based on the first mirror group. The position of G1 is divided into a wide angle (four) such as Guanlan state, a middle state, and a telephoto state. The first mirror group G2 has a positive refractive power and includes a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7 made of glass. The fourth lens L4 is a lenticular lens having a positive refractive power. The fifth lens L5 is a lenticular lens having a positive refractive power. The sixth lens L6 is a cemented lens having a negative refractive power, which is formed by a crescent lens L61 and a double concave lens L62; the concave surface R11 of the crescent lens L6]1 is directed to the imaging side, 15 201219825 The biconcave lens L62 is closer to the imaging side than the biconcave lens L62. The seventh lens is a lenticular lens having positive refractive power, and the surfaces R14 and R15 are aspherical surfaces. Further, the aperture ST of the short-focus projection lens 3 is located on the surface R14 of the seventh lens L7. In order to make the short-focus projection lens 3 energy-reducing the total length of the lens and correct the aberration, and the b-b has a longer post-focus and exit pUpii, and has better image quality, the short-focus projection lens 3 satisfies the following Conditions: (1) 1.88 <|fl/fw|< 2.58 (2) 2.9 < |f2/fw| < 3.3 (3) 3.16 < |fLl/fw| < 3.83 (4) 0.64 < |fA7f2| < 0.83 (5) 1.12<|e^f] < 135 (6) 0.035 < |n2/v2| < 0.043 where Π is the effective focal length of the first mirror group G1; f2 is the first The effective focal length of the two-mirror group G2; the effective focal length of the short-focus projection lens 3 in the wide-angle (four) de angle state; fLl is the effective focal length of the first lens L1; the effective focal length of the seventh lens L7; bf For the short focal projection lens 3, the focal length 'ex is the exit pupil position of the short focal projection lens 3; n2 is the refractive index of the second lens L2; ν2 is the dispersion coefficient of the second lens L2 . The focal length F (Focus Length), the numerical aperture fn 〇 (F-number) of the short-focus projection lens 3 of the second embodiment of the present invention, and the radius of curvature R of the optical axis z of each lens surface, The thickness T of the lens on the optical axis Z, the refractive index Nd (refractive index) of each lens, and the Abbe number of each lens are shown in Table 5: 201219825 F=10.1525(W)~ 11.0671(M)~12.1688(T)__FN0=2. 550(W)~2. 660(M)~2. 792(T) Surface R(mm) T(mm) Nd Vd Remarks R1 170.40 6.50 1.525 56.40 First Lens Ll_ R2 17.70 19.15 R3 -41.13 0.80 1.804 46. 57 Second lens L2 - R4 27.0 6.0(W)~6.415(M)~6.811(T) R5 57.40 6.47 1.648 33.79 Third lens L3 R6 -64. 20 17. 536(W)~11.882(M)~6. 035(T) R7 65.50 6.50 1.729 54. 68 Fourth lens L4 R8 -200.80 16.0 R9 18.38 4.49 1.497 81.55 Fifth lens L5- R10 -132.40 5. 80 R11 -65.17 2. 07 1.516 64.14 Sixth lens L6 R12 -12.94 0.80 1.834 37.16 —1 R13 50.30 2. 07 - R14 45.83 4.79 1.495 81.04 Seventh lens L7 aperture ST R15 -13.41 21.0 R16 Infinity 1.05 1.507 63.13 Glass cover R17 Infinity 3.411(W)~4. 663(M)~6.197(T) In the thickness T of Table 5, (W) means that the short-focus projection lens 3 is in a wide-angle state. When the short-focus projection lens 3 is in the middle state, the distance between the optical axes ;; (Τ) means that the short-focus projection lens 3 is long The distance between the optical axis Z and the distance from the telephoto state. In addition, the surface depression degree D of the aspherical surface, R2, R14 and r15 in the present embodiment is obtained by the following formula: C-H2 ^ + 1T^TkJ=^=^ + E^HA +E6'H6 +E^Ht +E^〇-Hl° +Εη·^'2 +Ε^·Η'Α +Ε16·Η16 where: D: the degree of depression of the aspherical surface; C: the reciprocal of the radius of curvature; 17 201219825 Η: Aperture radius of the surface; Κ = conical coefficient; Ε4~Ε16: various order coefficients of the aperture radius η of the surface. In this embodiment, the coefficient of the conical constant K and the surface aperture radius η of each aspheric surface are shown in Table 6 as shown in Table 6:
藉由上述的鏡片與光圈之配置，使得本實施例之短焦投影 鏡頭3不但可有效縮小體積以滿足輕量化之需求，該短焦投影 鏡頭3在廣角(wide_angle)狀態時，其成像品質上也可達到要 求’這可從圖10A至圖10D看出。 圖10A所示的’是本實施例之短焦投影鏡頭3的縱向色差 圖；圖10B所示的，是本實施例之短焦投影鏡頭3的橫向色 差圖；圖10C所示的，是本實施例之短焦投影鏡頭3的場曲 圖及畸變圖；圖l〇D所示的，是本實施例之短焦投影鏡頭3 的空間頻率調制傳遞函數圖（Spatial Frequency MTF)。從圖 10A及圖i〇B可看出，本實施例短焦投影鏡頭3之縱向色差最 大不超過〇.〇6mm和-〇.〇6mm，橫向色差最大不超過5μιη和 -3μηι。從圖10C可看出，本實施例短焦投影鏡頭3之最大場 201219825 曲不超過0.1〇mm與-0.10mm ’且畸變量不超過2%。從圖1〇D 可看出，本實施例短焦投影鏡頭3在80 lp/mm的時候，其調 制光學傳遞函數值仍維持在50%以上。 另外’該短焦投影鏡頭3在中間(middle)狀態時，其成像 品質上也可達到要求，這可從圖11A至圖11D看出。從圖11A 及圖11B可看出’本實施例短焦投影鏡頭3之縱向色差最大不 超過〇.〇4mm和-〇.〇5mm，橫向色差最大不超過5师和_2卿。 從圖11C可看出’本實施例短焦投影鏡頭3之最大場曲不超過 0.10mm與-〇.i〇mm，且畸變量不超過1 %。從圖11D可看出， 本實施例短焦投影鏡頭3在80 lp/mm的時候，其調制光學傳 遞函數值仍維持在50%以上。 再者’該短焦投影鏡頭3在長距投影(telephoto)狀態時， 其成像品質上也可達到要求，這可從圖12A至圖12D看出。 從圖12A及圖12B可看出，本實施例短焦投影鏡頭3之縱向 色差最大不超過〇.〇3mm和_〇 〇6mm，橫向色差最大不超過5μπι 和-Ιμιη。從圖12C可看出，本實施例短焦投影鏡頭3之最大 場曲不超過〇.l〇mm與_〇.1〇mm，且畸變量不超過i %。從圖 12D可看出，本實施例短焦投影鏡頭3在8〇 lp/mm的時候， 其調制光學傳遞函數值仍維持在4〇%以上。藉此，顯見本實施 例之短焦投影鏡頭3的解析度不管是在是廣角 態、中間(middle)狀態或是長距投影⑽eph〇t〇)狀態時，都是符 合標準的。 201219825 综合以上所述可得知，本發明之短焦投影鏡頭，不僅可達 到變焦之目的，且體積小更具高光學效能。 以上所述僅為本發明較佳可行實施例而已，舉凡應用本發 明說明書及申請專利範圍所為之等效結構及製作方法變化，理 應包含在本發明之專利範圍内。With the arrangement of the lens and the aperture described above, the short-focus projection lens 3 of the present embodiment can effectively reduce the volume to meet the demand for light weight, and the short-focus projection lens 3 has an image quality in a wide-angle state. The requirement can also be met 'this can be seen from Figures 10A to 10D. FIG. 10A is a longitudinal chromatic aberration diagram of the short-focus projection lens 3 of the present embodiment; FIG. 10B is a lateral chromatic aberration diagram of the short-focus projection lens 3 of the present embodiment; and FIG. 10C shows The field curvature diagram and the distortion diagram of the short-focus projection lens 3 of the embodiment; and the spatial frequency modulation transfer function diagram (Spatial Frequency MTF) of the short-focus projection lens 3 of the present embodiment are shown in FIG. As can be seen from Fig. 10A and Fig. 2B, the longitudinal chromatic aberration of the short-throw projection lens 3 of the present embodiment does not exceed 〇.〇6 mm and -〇.〇6 mm, and the lateral chromatic aberration does not exceed 5 μm and -3 μηι at the maximum. As can be seen from Fig. 10C, the maximum field 201219825 of the short-throw projection lens 3 of the present embodiment does not exceed 0.1 〇 mm and -0.10 mm' and the distortion variable does not exceed 2%. As can be seen from Fig. 1D, when the short-focus projection lens 3 of the present embodiment is at 80 lp/mm, the modulation optical transfer function value is maintained at 50% or more. Further, when the short-focus projection lens 3 is in the middle state, its image quality can also be achieved, which can be seen from Figs. 11A to 11D. As can be seen from Fig. 11A and Fig. 11B, the longitudinal chromatic aberration of the short-throw projection lens 3 of the present embodiment is not more than 〇.〇4 mm and -〇.〇5 mm, and the lateral chromatic aberration is not more than 5 divisions and _2 sec. As can be seen from Fig. 11C, the maximum field curvature of the short-throw projection lens 3 of the present embodiment does not exceed 0.10 mm and -〇.i〇mm, and the distortion variable does not exceed 1%. As can be seen from Fig. 11D, the value of the modulation optical transfer function of the short-throw projection lens 3 of this embodiment is maintained at 50% or more at 80 lp/mm. Furthermore, the short-focus projection lens 3 can also meet the imaging quality in the telephoto state, which can be seen from Figs. 12A to 12D. As can be seen from Figs. 12A and 12B, the longitudinal chromatic aberration of the short-focus projection lens 3 of the present embodiment does not exceed 〇.〇3 mm and _〇 〇6 mm at the maximum, and the lateral chromatic aberration does not exceed 5 μm and -Ιμιη at the maximum. As can be seen from Fig. 12C, the maximum field curvature of the short-throw projection lens 3 of the present embodiment does not exceed 〇.l〇mm and _〇.1〇mm, and the distortion variable does not exceed i%. As can be seen from Fig. 12D, when the short-focus projection lens 3 of the present embodiment is at 8 〇 lp/mm, the modulation optical transfer function value is maintained at 4% or more. Thereby, it is apparent that the resolution of the short-focus projection lens 3 of the present embodiment conforms to the standard regardless of whether it is in a wide-angle state, a middle state, or a long-distance projection (10) eph〇t〇 state. 201219825 In summary, it can be seen that the short-focus projection lens of the present invention not only achieves the purpose of zooming, but also has a small volume and high optical performance. The above description is only for the preferred embodiments of the present invention, and the equivalent structures and manufacturing methods of the present invention and the scope of the patent application are intended to be included in the scope of the present invention.
20 201219825 【圖式簡單說明】 圖1為本發明第—較佳實施例之鏡片配置圖。 圖2A為第—較佳實施例在廣角狀態時之縱向色差圖。 圖2B為第—較佳實施例在廣角狀態時之橫向色差圖。 圖2C為第—較佳實施例在廣角狀態時之場曲圖及畸變圖。 圖2D為第—較佳實施例在廣角狀態時之MTF圖。 圖3A為第—較佳實施例在中間狀態時之縱向色差圖。 圖3B為第—較佳實施例在中間狀態時之橫向色差圖。 圖3C為第—較佳實施例在中間狀態時之場賴及崎變圖。 圖3D為第一較佳實施例在中間狀態時之MTF圖。 圖4A為第—較佳實施例在遠距投影狀態時之縱向色差圖。 圖為第—錄實關在遠距投影狀騎之橫向色差圖。 圖4 C為第一較佳實施例在遠距投影狀態時之場曲圖及畸變圖。 圖4D為第—触實關在遠距郷狀態時之MTF圖。 圖5為本發明第二較佳實施例之鏡片配置圖。 圖6A為第二較佳實關在廣肖狀態時之縱向色差圖。 K6B為胃二較佳實施例在廣肖狀態時之橫向色差圖。 圖6C為第二較佳實施例在廣角狀態時之場曲圖及畸變圖。 圖6〇為第二較佳實施例在廣角狀態時之MTF圖。 圖7A為第二較佳實施例在中間狀態時之縱向色差圖。 圖7B為第二較佳實施例在中間狀態時之橫向色差圖。 圖7C為第二較佳實施例在中間狀態時之場曲圖及畸變圖。 21 201219825 圖7D為第二較佳實闕在t·態時之卿圖。 圖8A為第二較佳實施例在遠距投影狀態時之縱向色差圖。 圖邮為第二較佳實關在遠距投f彡狀ϋ時之橫向色差圖。 圖8為第—較佳實施例在遠距投影狀態時之場曲圖及崎變圖。 圖8D為第二較佳實施例在遠距投影狀態時之MTF圖。 圖9為本發明第三較佳實施例之鏡片配置圖。 圖10A為第三較佳實施例在廣触態時之縱向色差圖。 圖观騎三較佳實細在廣肖狀態時之橫向色差圖。 圖1〇C為第三較佳實施例在廣角狀態時之場曲圖及畸變圖。 圖1〇1)騎三較佳實施例在廣角狀態時之MTF圖。 圖11A為第三較佳實施例在中間狀態時之縱向色差圖。 圖11B為第三較佳實施例在中間狀態時之橫向色差圖。 圖11C為第二較佳實施例在中間狀態時之場曲圖及畸變圖。 圖UD為第三較佳實施例在中間狀態時之MTF圖。 圖12A為第三較佳實施例在遠距投影狀態時之縱向色差圖。 圖12B為第三較佳實施例在遠距投影狀態時之橫向色差圖。 圖12C為第三較佳實施例在遠距投影狀態時之場曲圖及畸變圖。 圖12D為第二較佳實施例在遠距投影狀態時之圖。 22 201219825 【主要元件符號說明】 1短焦投影鏡頭 G1第一鏡群 L1第一鏡片 G2第二鏡群 L4第四鏡片 L7第七鏡片 • CG玻璃覆蓋 Z光軸 2短焦投影鏡頭 G1第一鏡群 L1第一鏡片 G2第二鏡群 • L4第四鏡片 L7第七鏡片 CG玻璃覆蓋 Z光軸 L2第二鏡片 L5第五鏡片 L8第八鏡片 R1〜R18表面 L3第三鏡片 L6第六鏡片 L2第二鏡片 L5第五鏡片 L3第三鏡片 L6第六鏡片 R1〜R16表面 3短焦投影鏡頭 G1第一鏡群 L1第一鏡片 L2第二鏡片 L3第三鏡片 23 201219825 G2第二鏡群 L4第四鏡片 L5第五鏡片 L6第六鏡片 L61新月型透鏡L62雙凹透鏡 L7第七鏡片 CG玻璃覆蓋 R1〜R17表面 Z光轴20 201219825 BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a configuration diagram of a lens according to a first preferred embodiment of the present invention. Fig. 2A is a longitudinal chromatic aberration diagram of the first preferred embodiment in a wide-angle state. Fig. 2B is a lateral chromatic aberration diagram of the first preferred embodiment in the wide-angle state. 2C is a field curvature diagram and a distortion diagram of the first preferred embodiment in a wide-angle state. Fig. 2D is an MTF diagram of the first preferred embodiment in a wide-angle state. Fig. 3A is a longitudinal chromatic aberration diagram of the first preferred embodiment in an intermediate state. Fig. 3B is a lateral chromatic aberration diagram of the first preferred embodiment in the intermediate state. Fig. 3C is a field diagram and a map of the first preferred embodiment in an intermediate state. Figure 3D is an MTF diagram of the first preferred embodiment in an intermediate state. Figure 4A is a longitudinal chromatic aberration diagram of the first preferred embodiment in the telephoto state. The picture shows the first-recording in the lateral chromatic aberration diagram of the long-distance projection. 4C is a field curvature diagram and a distortion diagram of the first preferred embodiment in a telephoto state. Fig. 4D is an MTF diagram of the first-touch-off state in the remote state. Figure 5 is a perspective view of a lens configuration in accordance with a second preferred embodiment of the present invention. Fig. 6A is a longitudinal chromatic aberration diagram of the second preferred real-off state in a wide-axis state. K6B is a lateral chromatic aberration diagram of the preferred embodiment of the stomach 2 in the broad state. Fig. 6C is a field curvature diagram and a distortion diagram of the second preferred embodiment in a wide-angle state. Figure 6A is an MTF diagram of the second preferred embodiment in a wide-angle state. Fig. 7A is a longitudinal chromatic aberration diagram of the second preferred embodiment in an intermediate state. Fig. 7B is a lateral chromatic aberration diagram of the second preferred embodiment in an intermediate state. Fig. 7C is a field curvature diagram and a distortion diagram of the second preferred embodiment in an intermediate state. 21 201219825 Figure 7D is a diagram of the second preferred embodiment in the t state. Figure 8A is a longitudinal chromatic aberration diagram of the second preferred embodiment in the telephoto state. The map is the second best-practice diagram of the lateral chromatic aberration when the distance is thrown. Fig. 8 is a field curvature diagram and a sagittal diagram of the first preferred embodiment in a remote projection state. Figure 8D is an MTF diagram of the second preferred embodiment in a telephoto state. Figure 9 is a perspective view of a lens arrangement in accordance with a third preferred embodiment of the present invention. Fig. 10A is a longitudinal chromatic aberration diagram of the third preferred embodiment in a wide contact state. Fig. 3 is a lateral chromatic aberration diagram in the case of a wide-angle state. 1C is a field curvature diagram and a distortion diagram of the third preferred embodiment in a wide-angle state. Figure 1〇1) MTF diagram of the preferred embodiment of the rider in the wide-angle state. Figure 11A is a longitudinal chromatic aberration diagram of the third preferred embodiment in an intermediate state. Figure 11B is a lateral chromatic aberration diagram of the third preferred embodiment in an intermediate state. Figure 11C is a field curvature diagram and a distortion diagram of the second preferred embodiment in an intermediate state. Figure UD is an MTF diagram of the third preferred embodiment in an intermediate state. Figure 12A is a longitudinal chromatic aberration diagram of the third preferred embodiment in a telephoto state. Figure 12B is a lateral chromatic aberration diagram of the third preferred embodiment in the telephoto state. Fig. 12C is a field curvature diagram and a distortion diagram of the third preferred embodiment in a telephoto state. Figure 12D is a diagram of the second preferred embodiment in a telephoto state. 22 201219825 [Main component symbol description] 1 short focal projection lens G1 first mirror group L1 first lens G2 second mirror group L4 fourth lens L7 seventh lens • CG glass covered Z optical axis 2 short focal projection lens G1 first Mirror group L1 first lens G2 second mirror group L4 fourth lens L7 seventh lens CG glass cover Z optical axis L2 second lens L5 fifth lens L8 eighth lens R1 to R18 surface L3 third lens L6 sixth lens L2 second lens L5 fifth lens L3 third lens L6 sixth lens R1 to R16 surface 3 short focal projection lens G1 first mirror group L1 first lens L2 second lens L3 third lens 23 201219825 G2 second mirror group L4 Fourth lens L5 fifth lens L6 sixth lens L61 crescent lens L62 double concave lens L7 seventh lens CG glass cover R1 ~ R17 surface Z optical axis
24twenty four