A display substrate and a preparing method thereof, and a display apparatus are provided. The display substrate includes a display region and a peripheral region, wherein the peripheral region includes a circuit board pin region and a test pin region which are located on at least one side of the display region. The display substrate further includes: a plurality of sub-pixels, and a first power supply line electrically connected with the plurality of sub-pixels; at least one first bonding power supply pin, located in the circuit board pin region, electrically connected with the first power supply line, and configured to transmit a first power supply signal to the plurality of sub-pixels in a display stage; a second power supply line, located in the peripheral region and surrounding the display region.

A display substrate and a display device. The display substrate includes: a base substrate, which comprises a display region, a peripheral region and a barrier region, where the peripheral region surrounds the display region, and the display region surrounds the barrier region; a through hole located in the barrier region, the center of the display substrate not coinciding with the center of the through hole; a plurality of sub-pixels located in the display region; a plurality of signal lines that are located in the display region, the peripheral region and the barrier region, and are electrically connected to the plurality of sub-pixels; a shift register circuit that is located in the peripheral region and is electrically connected to the plurality of signal lines; and at least one circle of crack detection lines that are located in the barrier region and surround the through hole.

A display apparatus includes a display area including a display pixel having an emission area, a peripheral area which is outside of the display area, the peripheral area including a dam, and a first test pixel which is between the display area and the dam and has an emission area, and an encapsulation layer in the display area and extended from the display area to the dam The emission area of the first test pixel in the peripheral area is larger than the emission area of the display pixel in the display area.

An organic light emitting diode analyzer is provided to test electrical and spectroscopic characteristics organic light emitting diodes (OLED). The analyzer includes a spectrometer, a luminance and color meter, a header of the luminance and color meter, an OLED a source meter, an OLED holder and a computer. The OLED analyzer is a characterization system to measure the electrical and spectral characteristics and feature of the OLED. The luminance and color meter includes a color sensor, and the luminance and color meter measures a luminance of the OLED, a color temperature of the OLED, and color coordinates of the OLED. The spectrometer measures a wavelength of the OLED, an irradiance, a color index, the color temperature, color coordinates and the irradiance (W/m.sup.2.Math.nm). The source meter applies positive voltages to the OLED, and the source meter measures a current through the OLED.

A display is provided. The display device includes a display area and a non-display area located around the display area; a base layer; an organic light-emitting diode (OLED) that is located on the base layer in the display area; and a first crack detection line that is located on the base layer in the non-display area; wherein the first crack detection line comprises a first line that extends substantially in a first direction along a first edge of the display area, a second line that is separated from the first line and extends substantially in the first direction, and a third line that is connected to an end of the first line and an end of the second line, wherein a cross-sectional shape of the first line in a second direction crossing the first direction is inversely tapered.

A display is provided. The display device includes a display area and a non-display area located around the display area; a base layer; an organic light-emitting diode (OLED) that is located on the base layer in the display area; and a first crack detection line that is located on the base layer in the non-display area; wherein the first crack detection line comprises a first line that extends substantially in a first direction along a first edge of the display area, a second line that is separated from the first line and extends substantially in the first direction, and a third line that is connected to an end of the first line and an end of the second line, wherein a cross-sectional shape of the first line in a second direction crossing the first direction is inversely tapered.

In a printing method, at least one image of a substrate supported in a printing system is acquired. An actual position of a first alignment feature on the substrate in a frame of reference of the printing system is determined based on the at least one image. Expected positions of second alignment features on the substrate are determined based on the actual position of the first alignment feature. Actual positions of the second alignment features in the frame of reference of the printing system are determined based on the at least one image and the expected positions of the second alignment features. Target positions of print regions on the substrate are determined based on the actual positions of the second alignment features. Ejection of print material onto the substrate in the print regions is controlled based on the target positions of the print regions.

A light-emitting device, a material screening method and a display panel. The light-emitting device of a first aspect of the present application includes a light-emitting layer including a host material and a guest material. When a carrier is injected into the light-emitting layer, there is a defect energy Et between the host material and the guest material, and an absolute value of the defect energy Et is greater than or equal to 0.03 eV. A light-emitting efficiency of the light-emitting device in a high-luminance state is improved and an operating voltage of the light-emitting device is reduced, which can ensure a display quality of the display panel in the high-luminance state and reduce an overall power consumption of the display panel.

A light-emitting device, a material screening method and a display panel. The light-emitting device of a first aspect of the present application includes a light-emitting layer including a host material and a guest material. When a carrier is injected into the light-emitting layer, there is a defect energy Et between the host material and the guest material, and an absolute value of the defect energy Et is greater than or equal to 0.03 eV. A light-emitting efficiency of the light-emitting device in a high-luminance state is improved and an operating voltage of the light-emitting device is reduced, which can ensure a display quality of the display panel in the high-luminance state and reduce an overall power consumption of the display panel.

A display device includes a thin film layer test part capable of measuring a film quality of a deposited thin film layer, and the thin film layer test part includes a first wiring part formed at an upper surface of a thin film layer to be tested, pad parts connected to opposite ends of the first wiring part, a second wiring part formed at a lower surface of the thin film layer, and a pad part connected to the second wiring part, thus the display device can check a film quality of the thin film layer, for example, through detection of a resistance difference between the first wiring part and the second wiring part by the thin film layer test part.