the present invention will be described according to an embodiment thereof as follows : fig3 is a sectional view and a plan view showing the first embodiment of the present invention . two uniaxially stretched polyester films 12a , 12b each having a thickness t (= 100 μm ) and a polarizer 11 prepared by placing a dichroic pigment ( iodine , methyl red or the like ) into a pva ( polyvinyl alcohol ) type film are laminated by a polyester type adhesive to form each of composite films 13a and 13b . the composite films 13a , 13b are about 280 μm thick . a 400 å thick transparent conductive layer 14 ( a mixture of in 2 o 3 95 wt %, sno 2 5 wt % or the like ) is vacuumevaporated on the film surface at 70 ° c . by low temperature spattering . a display pattern is etched to form a substrate . next , a 2 % cyclohexanone solution of a polyamide resin type is coated on the display pattern surface by spinner and is dried at 100 ° c . for 10 minutes , forming an 800 å thick resin film . the film surface is rubbed in the direction of the polarization axis by use of a buffing cloth to form an orientation film 19 . after the rubbing treatment , the two substrates 13a , 13b are assembled using a sealant 21 with a combination of the rubbing directions such as shown in fig3 ( b ). reference numeral 22a represents the rubbing direction of the upper substrate 13a and 22b does that of the lower substrate 13b . the twist angle is 80 ° in this case . the sealant 21 is prepared by mixing a glass fiber 20 as a spacer with a polyester type adhesive . next , a liquid crystal 16 ( nematic liquid crystal &# 34 ; zli - 1132 &# 34 ; of merck co .) is sealed , thereby completing a transmission type display panel . the viewing direction of the resulting display panel is represented by reference numeral 23 and this display panel is suitable for a pocketable electronic calculator or for a game display panel . a reflection type display panel can be obtained by disposing a reflecting plate adjacent to the substrate 13b . in this embodiment , since the substrates 13a , 13b are composed of the uniaxially stretched polyester film , all the aforementioned requirements ( 1 ) through ( 7 ) imposed on the display panel can be altogether satisfied . since the display member consists of the liquid crystal , further , the requirements ( 8 ) and ( 9 ) can be also satisfied , and the requirement ( 7 ) can be satisfied if the display panel is of the reflection type . since the substrates 13a , 13b are equipped with the polarizers 11 , they also serve as the polarizing plates , thus making it possible to reduce the size of the display panel . in this instance , the polarizer 11 , which is otherwise weak both mechanically and chemically , is interposed between the two uniaxially stretched polyester films 12 , all the mechanical strength , acid resistance , alkali resistance , heat resistance , liquid crystal dissolution resistance and solvent resistance can be improved . next , detailed explanation will be made on the difference of the light transmittance between the uniaxially stretched polyester film to be used in this embodiment and the biaxially stretched polyester film which shows the second best characteristics in table 1 . table 2 illustrates the results of measurement of the refractive indices n a , n b and n c between the uniaxially stretched film used in the present invention and the biaxially stretched polyester film used in the prior art . table 2______________________________________ biaxially stretched uniaxially stretched polyester film polyester film______________________________________n . sub . a 1 . 67 & gt ; 1 . 7n . sub . b 1 . 62 1 . 60n . sub . c 1 . 49 1 . 49______________________________________ the difference δn ab between n a (= n s ) and n b is greater in for the uniaxially stretched polyester film . when the composite film 13 such as shown in fig3 is produced using such an optically anisotropic , uniaxially stretched polyester film , the angles θ 1 , θ 2 defined between the direction d of the axis of polarization of the polarizer 11 and the slow and fast principal axis of the uniaxially stretched polyester film 12 , which as the greatest refractive index among the three principal axes , as shown in fig4 become important . for , when an optically anisotropic member is combined with the polarizer 11 , the color of interference would occur due to birefringence unless a suitable combination is selected . in such a case , the contrast ratio would drop and the display quality would be remarkably reduced . in the first embodiment of the present invention shown in fig3 the difference between θ 1 and θ 2 is within ± 3 ° for the following reasons . fig5 is a diagram showing the wavelength dependence of the light transmittance when the light is incident at right angles ( φ = 0 ) to the main surfaces of the uniaxially stretched polyester films 12a , 12b in the liquid crystal display shown in fig3 . fig5 ( a ) shows the case when a 100 μm thick uniaxially stretched polyester film is used and fig5 ( b ) shows the case when a 100 μm thick biaxially stretched polyester film of the prior art is used . when the θ 1 and θ 2 values are zero degree , the wavelength characteristics of the light transmittance show the flat characteristics but as these values become greater , the light transmittance ratio decreases due to birefringence . fig6 shows the integration value of the wavelength characteristics of fig5 that is , the θ 1 , θ 2 dependence of the light transmittance ratio for the white light . symbols ( a ) and ( b ) represent the uniaxially stretched polyester film and the biaxially stretched polyester film , respectively . as can be understood from the diagram , the light transmittance of the uniaxially stretched polyester film drops markedly when the values θ 1 and θ 2 become greater than ± 3 ° and the light transmittance of the biaxially stretched polyester film decreases when the values become greater than ± 5 °. when the uniaxially stretched polyester film is used , therefore , the light transmittance becomes at least 95 % and equal to that of the glass sheet when either of the two uniaxially stretched polyester films 12a and 12b , which has the greatest refractive index in the direction of the slow and fast principal axes of birefringence , is disposed so that the angle defined between it and the direction of the axis of polarization of the polarizer 11 is within ± 3 °, and when the biaxially stretched polyester film is used , the light transmittance becomes at least 95 % and equal to that of the glass sheet if this angle is within ± 5 °. fig7 is a diagram showing the relation between the thickness t of the stretched polyester films 12a , 12b and the light transmittance when φ = 40 °. fig7 ( a ) shows the case in which the uniaxially stretched polyester film is used in such a manner that θ 1 and θhd 2 are within ± 3 ° while fig7 ( b ) shows the case in which the biaxially stretched polyester film of the prior art is used in such a manner that θ 1 and θ 2 are within ± 5 °. when the uniaxially stretched polyester film is used so that the values of the angles θ 1 and θ 2 defined between the direction d of the axis of polarization of the polarizer 11 and the direction a of the slow and fast principal axes of birefringence of the stretched film are within ± 3 °, the occurrence of the color of interference resulting from birefringence and hence , the drop of display quality , can be eliminated . even if the θ 1 , θ 2 values of the biaxially stretched polyester films are set within ± 5 °, on the other hand , the light transmittance would drop due to birefringence if the film thickness t exceeds 50 μm . this phenomenon is believed to result from the fact that molecular orientation within the film surfaces develops also in the direction perpendicular to the direction of the axis of polarization of the polarizer due to biaxial stretching . the viewing angle properties of the stretched polyester films 12a , 12b per se will be explained with reference to fig8 through 10 in order to further clarify the difference between the biaxially stretched polyester film and the uniaxially stretched polyester film . in fig8 the stretched polyester film 12 , the polarizers 11a , 11b and an analyzer 20 are arranged in such a fashion that the light transmitting through the polarizer 11a is incident to the stretched polyester film 12 and the light passing through the stretched polyester film 12 and the polarizer 11b is detected by the analyzer 20 . in this case , the direction d of the axes of polarization of the polarizers 11a , 11b is the same as the angle θ of the direction of one b of the slow and fast principal axes of birefringence of the stretched polyester film 12 . fig9 shows the dependence of the light transmittance upon the angle of incidence φ measured by the analyzer 20 when the direction d of the axis of polarization is in agreement with the direction of the slow and fast principal axes of birefringence a , b of the biaxially stretched polyester film 12 . similarly , fig1 shows the dependence when the uniaxially stretched polyester film is used . in fig9 and 10 , symbol ( a ) represents the case in which the direction d of the axes of polarization 11a , 11b is in agreement with one b of the slow and fast principal axes of birefringence ( that is , θ = 0 °) and ( b ) does the case in which it is in agreement with the other of the slow and fast principal axes of birefringence ( that is , θ = 90 °). it can be seen by comparing these diagrams that the light transmittance does not much change even if the angle of incidence φ becomes great in the case of the uniaxially stretched polyester film shown in fig1 but it drastically drops in the case of the biaxially stretched polyester film shown in fig9 if the absolute value | φ | becomes 30 ° or more . particularly when θ = 90 °, this tendency becomes all the more remarkable . it can be thus understood that the dependence upon the angle of incidence is smaller and the viewing characteristics are better in the uniaxially stretched polyester film than in the biaxially stretched polyester film . this embodiment exhibits substantially the same performance as a display panel using the glass sheet ( optically isotropic material ). fig1 is a diagram showing the voltage dependence of brightness at each angle of incidence φ when the light is incident to the main surface of a tn type liquid crystal panel at the angle of incidence φ . fig1 shows the voltage dependence in the case of the biaxially stretched polyester film of the prior art and fig1 does that of the glass sheet of the prior art . in fig1 through 13 , the applied voltage is a 1 khz square wave alternating current and the voltage is raised from 0 v to 4 v at a rate of approximately 1 . 5 v / min . it can be seen by comparing fig1 with fig1 that the embodiments of the present invention exhibits substantially the same performance as that of the display panel using the glass sheet ( optically isotropic material ) as the substrates . the embodiment provides a display panel in which the drop of the light transmittance due to interference is lesser , the contrast ratio is greater and the display quality is higher than the display panel using the biaxialy stretched polyester film of the prior art . fig1 shows the second embodiment of the present invention which is the same as the first embodiment shown in fig3 except that the outer uniaxially stretched polyester film 12a is not disposed . this embodiment can accomplish the same effect as that of the first embodiment . fig1 shows the third embodiment of the present invention which uses a quest - host type liquid crystal 16 ( which is prepared , for example , by mixing a &# 34 ; pch type liquid crystal zli - 1132 &# 34 ; of merck co . with a 94 wt % cholesteric liquid crystal &# 34 ; cb - 15 &# 34 ; and a 3 wt % dichroic dye &# 34 ; gb - 10 &# 34 ;). this embodiment is the same as the first embodiment except that the polarizer 11 is disposed on only one 13a of the substrates . the same effect as that of the first embodiment can also be accomplished in this embodiment . a preferred example of the uniaxially stretched polyester film to be used in the present invention is a uniaxially stretched polyethylene terephthalate film but films made of uniaxially stretched polyethylene isophthalate , uniaxially stretched polyphenylene isophthalate , polybutylene terephthalate and the like may also be used . among the pair of substrates , one may be composed of the uniaxially stretched polyester film with the other consisting of glass or the like , and a strong dielectric may also be used as the display member . it is to be understood by those skilled in the art that the foregoing description is some preferred embodiments of the invention and various changes and modifications may be made without departing from the spirit and scope thereof .